WO2024182915A1

WO2024182915A1 - Element grouping for a reconfigurable intelligent surface

Info

Publication number: WO2024182915A1
Application number: PCT/CN2023/079467
Authority: WO
Inventors: Min Huang; Mingxi YIN; Hao Xu
Original assignee: Qualcomm Incorporated
Priority date: 2023-03-03
Filing date: 2023-03-03
Publication date: 2024-09-12

Abstract

Methods, systems, and devices for wireless communication are described. A reconfigurable intelligent surface (RIS) may transmit a capability message to a network entity that may indicate one or more supported RIS element grouping types. The network entity may transmit a grouping message to the RIS and a user equipment (UE) that may indicate a selected RIS element grouping type and set of resources allocated for reflection of one or more signals. The RIS may reflect the one or more signals to the UE according to the selected RIS element grouping type during the set of resources. The UE may perform channel estimation measurements on the one or more signals based on the RIS element grouping type indicated in the grouping message. The UE may determine a reflection coefficient for each RIS element group and may report a set of reflection coefficients to the network entity.

Description

ELEMENT GROUPING FOR A RECONFIGURABLE INTELLIGENT SURFACE

FIELD OF TECHNOLOGY

The following relates to wireless communication, including element grouping for a reconfigurable intelligent surface (RIS) .

BACKGROUND

Wireless communications systems are widely deployed to provide various types of communication content such as voice, video, packet data, messaging, broadcast, and so on. These systems may be capable of supporting communication with multiple users by sharing the available system resources (e.g., time, frequency, and power) . Examples of such multiple-access systems include fourth generation (4G) systems such as Long Term Evolution (LTE) systems, LTE-Advanced (LTE-A) systems, or LTE-A Pro systems, and fifth generation (5G) systems which may be referred to as New Radio (NR) systems. These systems may employ technologies such as code division multiple access (CDMA) , time division multiple access (TDMA) , frequency division multiple access (FDMA) , orthogonal FDMA (OFDMA) , or discrete Fourier transform spread orthogonal frequency division multiplexing (DFT-S-OFDM) . A wireless multiple-access communications system may include one or more base stations, each supporting wireless communication for communication devices, which may be known as user equipment (UE) .

Some wireless communications systems may include one or more reconfigurable intelligent surfaces (RISs) to facilitate transmissions between wireless devices. A RIS may include a quantity of reflective elements operable to reflect or refract transmissions in a certain direction based on a configuration of the elements.

SUMMARY

The described techniques relate to improved methods, systems, devices, and apparatuses that support element grouping for a reconfigurable intelligent surface (RIS) . For example, the described techniques enable dynamic RIS element grouping based on RIS capability and available radio resources. The RIS may transmit a capability message to a network entity that indicates one or more element group types supported by the RIS. The network entity may transmit a message to the RIS and a user equipment (UE) that indicates a RIS element grouping type selected from the one or more element group types indicated in the capability message and indicates a set of resources allocated for reflection of one or more signals. The RIS may operate according to the selected grouping type using the set of resources. That is, the UE may receive one or more signals that are at least partially reflected by the RIS via the set of resources and may perform measurements (e.g., channel estimation measurements) on the one or more signals. The UE may transmit a channel state information (CSI) report to the network entity that indicates a quantity of reflection coefficients each corresponding to a respective RIS element group.

A method for wireless communication at a RIS is described. The method may include transmitting a capability message that indicates one or more element grouping types supported by the RIS, where each of the one or more element grouping types corresponds to a respective pattern for grouping a set of multiple elements of the RIS, receiving a message that indicates an element grouping type for the RIS, the element grouping type selected from the one or more element grouping types indicated via the capability message and a set of resources allocated for reflection of one or more signals using the element grouping type, and operating, during the set of resources, in accordance with the element grouping type indicated via the message.

An apparatus for wireless communication at a RIS is described. The apparatus may include a processor, memory coupled with the processor, and instructions stored in the memory. The instructions may be executable by the processor to cause the apparatus to transmit a capability message that indicates one or more element grouping types supported by the RIS, where each of the one or more element grouping types corresponds to a respective pattern for grouping a set of multiple elements of the RIS, receive a message that indicates an element grouping type for the RIS, the element grouping type selected from the one or more element grouping types indicated via the capability message and a set of resources allocated for reflection of one or more signals using the element grouping type, and operate, during the set of resources, in accordance with the element grouping type indicated via the message.

Another apparatus for wireless communication at a RIS is described. The apparatus may include means for transmitting a capability message that indicates one or more element grouping types supported by the RIS, where each of the one or more element grouping types corresponds to a respective pattern for grouping a set of multiple elements of the RIS, means for receiving a message that indicates an element grouping type for the RIS, the element grouping type selected from the one or more element grouping types indicated via the capability message and a set of resources allocated for reflection of one or more signals using the element grouping type, and means for operating, during the set of resources, in accordance with the element grouping type indicated via the message.

A non-transitory computer-readable medium storing code for wireless communication at a RIS is described. The code may include instructions executable by a processor to transmit a capability message that indicates one or more element grouping types supported by the RIS, where each of the one or more element grouping types corresponds to a respective pattern for grouping a set of multiple elements of the RIS, receive a message that indicates an element grouping type for the RIS, the element grouping type selected from the one or more element grouping types indicated via the capability message and a set of resources allocated for reflection of one or more signals using the element grouping type, and operate, during the set of resources, in accordance with the element grouping type indicated via the message.

Some examples of the method, apparatuses, and non-transitory computer-readable medium described herein may further include operations, features, means, or instructions for receiving a second message that indicates a group-based beamforming weight and a corresponding second element grouping type to be applied for subsequent operations by the RIS, where the group-based beamforming weight may be based on operations by the RIS during the set of resources, and where the group-based beamforming weight includes a set of multiple reflection coefficients each associated with a respective element group of a set of one or more element groups associated with the second element grouping type and operating, during a second set of resources that may be after the set of resources in time, in accordance with the group-based beamforming weight and the corresponding second element grouping type indicated via the second message.

In some examples of the method, apparatuses, and non-transitory computer-readable medium described herein, receiving the second message may include operations, features, means, or instructions for receiving, via the second message, an indication of an index of the second element grouping type from among a set of indices associated with the one or more element grouping types indicated via the capability message.

In some examples of the method, apparatuses, and non-transitory computer-readable medium described herein, receiving the second message may include operations, features, means, or instructions for receiving, via the second message, an indication of an identifier of a resource from among the set of resources, where the group-based beamforming weight and the second element grouping type may be based on the identified resource.

In some examples of the method, apparatuses, and non-transitory computer-readable medium described herein, transmitting the capability message may include operations, features, means, or instructions for transmitting, for each element grouping type of the one or more element grouping types supported by the RIS, an indication of a quantity of element groups associated with the respective element grouping type, where a quantity of elements included in each element group of the quantity of element groups may be based on a total quantity of elements of the set of multiple elements of the RIS and the quantity of element groups, and where the quantity of elements included in each element group may be the same.

In some examples of the method, apparatuses, and non-transitory computer-readable medium described herein, transmitting the capability message may include operations, features, means, or instructions for transmitting, for each element grouping type of the one or more element grouping types supported by the RIS, an indication of a quantity of element groups associated with the respective element grouping type and a quantity of elements included in each element group of the quantity of element groups, where the quantity of elements in each element group may be the same or different.

In some examples of the method, apparatuses, and non-transitory computer-readable medium described herein, transmitting the capability message may include operations, features, means, or instructions for transmitting, for each element grouping type of the one or more element grouping types supported by the RIS, an indication of a total quantity of elements of the set of multiple elements of the RIS, a quantity of element groups associated with the respective element grouping type, and a ratio associated with each element group of the quantity of element groups, where a quantity of elements included in each element group may be based on a product of a respective ratio associated with the element group and the total quantity of elements of the RIS.

In some examples of the method, apparatuses, and non-transitory computer-readable medium described herein, receiving the message may include operations, features, means, or instructions for receiving, via the message, an index of the element grouping type from among the one or more element grouping types indicated via the capability message, where the element grouping type may be selected from among the one or more element grouping types based on a quantity of resources included in the set of resources allocated for the reflection of the one or more signals, and where the element grouping type may be associated with a first quantity of element groups, receiving, via the message, an indication of an expanding factor associated with the element grouping type, the expanding factor including a number greater than or equal to one, where the expanding factor may be based on the quantity of resources, and operating using a second quantity of element groups of the RIS in accordance with the element grouping type and the expanding factor, where the second quantity may be based on a ratio of the first quantity of element groups associated with the element grouping type and the expanding factor.

In some examples of the method, apparatuses, and non-transitory computer-readable medium described herein, the message may indicate a pattern for alternating between a quantity of element groups associated with the element grouping type, and operating in accordance with the element grouping type may include operations, features, means, or instructions for activating, during each resource of the set of resources in accordance with the pattern, a respective element group of the quantity of element groups associated with the element grouping type, where a quantity of resources included in the set of resources may be the same as the quantity of element groups, and where activating the respective element group of the RIS during each resource may be based on the message indicating a per-element on-off channel estimation type.

In some examples of the method, apparatuses, and non-transitory computer-readable medium described herein, the message may indicate a pattern for alternating between a quantity of element groups associated with the element grouping type, and operating in accordance with the element grouping type may include operations, features, means, or instructions for activating, during each resource of the set of resources in accordance with the pattern, the quantity of element groups of the RIS and applying, during each resource of the set of resources in accordance with the pattern, a respective reflection coefficient from among a set of candidate reflection coefficients to each element group of the quantity of element groups, where applying the respective reflection coefficients may be based on the message indicating a least squared (LS) channel estimation type or a compressive sensing (CS) channel estimation type.

Some examples of the method, apparatuses, and non-transitory computer-readable medium described herein may further include operations, features, means, or instructions for generating, during each resource of the set of resources, a respective group-based beamforming weight based on applying one or more respective reflection coefficients to the quantity of element groups.

In some examples of the method, apparatuses, and non-transitory computer-readable medium described herein, operating in accordance with the element grouping type may include operations, features, means, or instructions for reflecting a set of one or more signals during the set of resources in accordance with the element grouping type.

In some examples of the method, apparatuses, and non-transitory computer-readable medium described herein, transmitting the capability message and receiving the message may include operations, features, means, or instructions for transmitting, using a controller of the RIS, the capability message and receiving, using the controller of the RIS, the message.

A method for wireless communication at a network entity is described. The method may include receiving a capability message that indicates one or more element grouping types supported by a RIS, where each of the one or more element grouping types corresponds to a respective pattern for grouping a set of multiple elements of the RIS, transmitting a message that indicates an element grouping type for the RIS, the element grouping type selected from the one or more element grouping types indicated via the capability message and a set of resources allocated for reflection of one or more signals using the element grouping type, and transmitting the one or more signals during the set of resources.

An apparatus for wireless communication at a network entity is described. The apparatus may include a processor, memory coupled with the processor, and instructions stored in the memory. The instructions may be executable by the processor to cause the apparatus to receive a capability message that indicates one or more element grouping types supported by a RIS, where each of the one or more element grouping types corresponds to a respective pattern for grouping a set of multiple elements of the RIS, transmit a message that indicates an element grouping type for the RIS, the element grouping type selected from the one or more element grouping types indicated via the capability message and a set of resources allocated for reflection of one or more signals using the element grouping type, and transmit the one or more signals during the set of resources.

Another apparatus for wireless communication at a network entity is described. The apparatus may include means for receiving a capability message that indicates one or more element grouping types supported by a RIS, where each of the one or more element grouping types corresponds to a respective pattern for grouping a set of multiple elements of the RIS, means for transmitting a message that indicates an element grouping type for the RIS, the element grouping type selected from the one or more element grouping types indicated via the capability message and a set of resources allocated for reflection of one or more signals using the element grouping type, and means for transmitting the one or more signals during the set of resources.

A non-transitory computer-readable medium storing code for wireless communication at a network entity is described. The code may include instructions executable by a processor to receive a capability message that indicates one or more element grouping types supported by a RIS, where each of the one or more element grouping types corresponds to a respective pattern for grouping a set of multiple elements of the RIS, transmit a message that indicates an element grouping type for the RIS, the element grouping type selected from the one or more element grouping types indicated via the capability message and a set of resources allocated for reflection of one or more signals using the element grouping type, and transmit the one or more signals during the set of resources.

Some examples of the method, apparatuses, and non-transitory computer-readable medium described herein may further include operations, features, means, or instructions for receiving, based on the one or more signals, a CSI report that indicates a group-based beamforming weight, where the group-based beamforming weight may be based on operations by the RIS during the set of resources, and where the group-based beamforming weight includes a set of multiple reflection coefficients each associated with a respective element group of a set of one or more element groups of the RIS and transmitting, based on the CSI report, a second message that indicates the group-based beamforming weight and a corresponding second element grouping type to be applied for subsequent operations by the RIS.

In some examples of the method, apparatuses, and non-transitory computer-readable medium described herein, transmitting the second message may include operations, features, means, or instructions for transmitting, via the second message, an indication of an index of the second element grouping type from among a set of indices associated with the one or more element grouping types indicated via the capability message.

In some examples of the method, apparatuses, and non-transitory computer-readable medium described herein, transmitting the second message may include operations, features, means, or instructions for transmitting, via the second message, an indication of an identifier of a resource from among the set of resources, where the group-based beamforming weight and the second element grouping type may be based on the identified resource.

In some examples of the method, apparatuses, and non-transitory computer-readable medium described herein, receiving the capability message may include operations, features, means, or instructions for receiving, for each element grouping type of the one or more element grouping types supported by the RIS, information that indicates a quantity of element groups associated with the respective element grouping type and a quantity of elements included in each element group of the one or more element groups.

In some examples of the method, apparatuses, and non-transitory computer-readable medium described herein, transmitting the message may include operations, features, means, or instructions for transmitting, via the message, an index of the element grouping type from among the one or more element grouping types indicated via the capability message, where the element grouping type may be based on a quantity of resources included in the set of resources allocated for the reflection of the one or more signals, and where the element grouping type may be associated with a first quantity of element groups and transmitting, via the message, an indication of an expanding factor associated with the element grouping type, the expanding factor including a number greater than or equal to one, where the expanding factor may be based on the quantity of resources, and where a second quantity of element groups for operations by the RIS may be based on a ratio of the first quantity of element groups associated with the element grouping type and the expanding factor.

In some examples of the method, apparatuses, and non-transitory computer-readable medium described herein, transmitting the message may include operations, features, means, or instructions for transmitting, via the message, an indication of a pattern for alternating, by the RIS during the set of resources, between a quantity of element groups of the set of multiple elements of the RIS associated with the element grouping type and between corresponding reflection coefficients, where the pattern may be based on a channel estimation type associated with the one or more signals.

Some examples of the method, apparatuses, and non-transitory computer-readable medium described herein may further include operations, features, means, or instructions for transmitting a second message that indicates a type of channel estimation associated with the one or more signals and a quantity of element groups that may be associated with the element grouping type for the RIS, where the type of channel estimation includes a per-element on-off channel estimation type, a LS channel estimation type, or a CS channel estimation type.

In some examples of the method, apparatuses, and non-transitory computer-readable medium described herein, transmitting the one or more signals may include operations, features, means, or instructions for transmitting the one or more signals for reflection by the RIS to a user equipment (UE) in accordance with the element grouping type.

A method for wireless communication at a UE is described. The method may include receiving a message that indicates an element grouping type for operations by a RIS during a set of resources, where the RIS includes a set of multiple elements that support reflection of wireless signals, and where the element grouping type corresponds to a respective pattern for grouping the set of multiple elements of the RIS into one or more element groups, receiving one or more signals during the set of resources, where the one or more signals are at least partially reflected by the RIS in accordance with the element grouping type, and transmitting a CSI report that indicates a set of multiple reflection coefficients based on measurements of the one or more signals, where each reflection coefficient of the set of multiple reflection coefficients corresponds to a respective group of the one or more element groups of the set of multiple elements of the RIS.

An apparatus for wireless communication at a UE is described. The apparatus may include a processor, memory coupled with the processor, and instructions stored in the memory. The instructions may be executable by the processor to cause the apparatus to receive a message that indicates an element grouping type for operations by a RIS during a set of resources, where the RIS includes a set of multiple elements that support reflection of wireless signals, and where the element grouping type corresponds to a respective pattern for grouping the set of multiple elements of the RIS into one or more element groups, receive one or more signals during the set of resources, where the one or more signals are at least partially reflected by the RIS in accordance with the element grouping type, and transmit a CSI report that indicates a set of multiple reflection coefficients based on measurements of the one or more signals, where each reflection coefficient of the set of multiple reflection coefficients corresponds to a respective group of the one or more element groups of the set of multiple elements of the RIS.

Another apparatus for wireless communication at a UE is described. The apparatus may include means for receiving a message that indicates an element grouping type for operations by a RIS during a set of resources, where the RIS includes a set of multiple elements that support reflection of wireless signals, and where the element grouping type corresponds to a respective pattern for grouping the set of multiple elements of the RIS into one or more element groups, means for receiving one or more signals during the set of resources, where the one or more signals are at least partially reflected by the RIS in accordance with the element grouping type, and means for transmitting a CSI report that indicates a set of multiple reflection coefficients based on measurements of the one or more signals, where each reflection coefficient of the set of multiple reflection coefficients corresponds to a respective group of the one or more element groups of the set of multiple elements of the RIS.

A non-transitory computer-readable medium storing code for wireless communication at a UE is described. The code may include instructions executable by a processor to receive a message that indicates an element grouping type for operations by a RIS during a set of resources, where the RIS includes a set of multiple elements that support reflection of wireless signals, and where the element grouping type corresponds to a respective pattern for grouping the set of multiple elements of the RIS into one or more element groups, receive one or more signals during the set of resources, where the one or more signals are at least partially reflected by the RIS in accordance with the element grouping type, and transmit a CSI report that indicates a set of multiple reflection coefficients based on measurements of the one or more signals, where each reflection coefficient of the set of multiple reflection coefficients corresponds to a respective group of the one or more element groups of the set of multiple elements of the RIS.

In some examples of the method, apparatuses, and non-transitory computer-readable medium described herein, receiving the message may include operations, features, means, or instructions for receiving, via the message, an indication of a quantity of element groups included in the one or more element groups of the RIS, a quantity of elements included in each group of the one or more element groups, or both.

Some examples of the method, apparatuses, and non-transitory computer-readable medium described herein may further include operations, features, means, or instructions for estimating a channel based on the measurements of the one or more signals and determining a group-based beamforming weight associated with the RIS based on the estimated channel, where the group-based beamforming weight includes the set of multiple reflection coefficients, and where transmitting the CSI report may be based on determining the group-based beamforming weight.

In some examples of the method, apparatuses, and non-transitory computer-readable medium described herein, estimating the channel may include operations, features, means, or instructions for estimating the channel in accordance with a channel estimation type selected from one of a per-element on-off channel estimation type, a LS channel estimation type, or a CS channel estimation type.

Some examples of the method, apparatuses, and non-transitory computer-readable medium described herein may further include operations, features, means, or instructions for receiving, during a second set of resources that may be after the set of resources in time, one or more second signals that may be at least partially reflected by the RIS in accordance with the set of multiple reflection coefficients indicated via the CSI report.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates an example of a wireless communications system that supports element grouping for a reconfigurable intelligent surface (RIS) in accordance with one or more aspects of the present disclosure.

FIG. 2 illustrates an example of a wireless communications system that supports element grouping for a RIS in accordance with one or more aspects of the present disclosure.

FIG. 3 illustrates examples of RIS hardware configurations that support element grouping for a RIS in accordance with one or more aspects of the present disclosure.

FIG. 4 illustrates examples of RIS element grouping configurations that support element grouping for a RIS in accordance with one or more aspects of the present disclosure.

FIG. 5 illustrates an example of a process flow that supports element grouping for a RIS in accordance with one or more aspects of the present disclosure.

FIGs. 6 and 7 illustrate block diagrams of devices that support element grouping for a RIS in accordance with one or more aspects of the present disclosure.

FIG. 8 illustrates a block diagram of a communications manager that supports element grouping for a RIS in accordance with one or more aspects of the present disclosure.

FIG. 9 illustrates a diagram of a system including a device that supports element grouping for a RIS in accordance with one or more aspects of the present disclosure.

FIGs. 10 and 11 illustrate block diagrams of devices that support element grouping for a RIS in accordance with one or more aspects of the present disclosure.

FIG. 12 illustrates a block diagram of a communications manager that supports element grouping for a RIS in accordance with one or more aspects of the present disclosure.

FIG. 13 illustrates a diagram of a system including a device that supports element grouping for a RIS in accordance with one or more aspects of the present disclosure.

FIGs. 14 and 15 illustrate block diagrams of devices that support element grouping for a RIS in accordance with one or more aspects of the present disclosure.

FIG. 16 illustrates a block diagram of a communications manager that supports element grouping for a RIS in accordance with one or more aspects of the present disclosure.

FIG. 17 illustrates a diagram of a system including a device that supports element grouping for a RIS in accordance with one or more aspects of the present disclosure.

FIGs. 18 through 20 illustrate flowcharts showing methods that support element grouping for a RIS in accordance with one or more aspects of the present disclosure.

DETAILED DESCRIPTION

Some wireless communications systems may include one or more reconfigurable intelligent surfaces (RISs) that reflect communications between devices (e.g., around blockages) . A RIS may include a quantity of elements (e.g., unit cells, scattering units, antenna elements, meta-elements, or other elements) that are operable to reflect or refract communications between devices. A user equipment (UE) that receives signals reflected by a RIS may use one or more methods for estimating the reflected channel (e.g., per-element on-off, least square (LS) , compressive sensing (CS) , or other channel estimation techniques) . However, to accurately support channel estimation, a quantity of resources allocated for channel estimation may be the same as a quantity of RIS elements, which may increase radio resource consumption and processing complexity. The RIS may group the RIS elements into several element groups, where each group may act as a virtual element to reduce resource consumption, but such element grouping may reduce RIS reflection beamforming gain, in some cases.

Accordingly, aspects of the techniques described herein provide more efficient and reliable RIS element grouping indications. These techniques leverage signaling to facilitate RIS element grouping for channel estimation based on a capability of the RIS and a quantity of available channel estimation resources. The RIS may transmit a capability report to a network entity that indicates one or more element group types supported by the RIS (e.g., according to hardware configuration of the RIS) . Each element group type may indicate a respective quantity of groups supported by the RIS and a quantity of elements in each group. The network entity may determine an element grouping type for the RIS to use when reflecting signals to a UE based on the one or more element grouping types indicated via the RIS capability and a quantity of available channel estimation resources to balance resource consumption with beamforming gain.

The network entity may transmit an indication of the determined grouping type and corresponding resources that are allocated for reflection of signals by the RIS using the grouping type to the RIS and to the UE. The RIS may configure the RIS elements according to the grouping type during the resources. The network entity may transmit the signals for at least partial reflection or refraction by the RIS during the resources, and the UE may perform channel estimation based on measurements of the reflected signals and the element grouping type. The UE may determine a set of reflection coefficients for the RIS to use for reflecting subsequent communications based on the channel estimation and may report the reflection coefficients back to the network entity (e.g., via a channel state information (CSI) report) . The network entity may forward the set of reflection coefficients received from the UE to the RIS, and the RIS may operate according to the indicated grouping type and corresponding reflection coefficients during subsequent resources. For example, the RIS may apply each reflection coefficient to a respective element group during the subsequent resources.

Particular aspects of the subject matter described in this disclosure may be implemented to realize one or more of the following potential advantages. In some examples, by accounting for RIS capabilities and available radio resources when selecting a RIS grouping configuration, a network entity may achieve a balance between processing complexity, resource consumption, and RIS beamforming gain. For example, the network entity may refrain from indicating a RIS element grouping type that is not supported by hardware at the RIS, which may improve coordination between devices and communication reliability. The network entity may, in some examples, scale or adjust a grouping type indicated by the RIS to include fewer groups and more elements per group based on a quantity of available resources, which may provide for improved resource utilization and throughput. In some examples, a UE may perform a channel estimation based on signals reflected by the RIS, and the UE may indicate an measurements or parameters (e.g., a beamforming weight) for application by the RIS. The network entity may forward the indication to the RIS for subsequent communications, which may improve throughput and communication reliability relative to systems in which the RIS element grouping is not based on UE feedback.

Aspects of the disclosure are initially described in the context of wireless communications systems. Aspects of the disclosure are further described with reference to RIS hardware configurations, RIS element grouping configurations, and a process flow Aspects of the disclosure are further illustrated by and described with reference to apparatus diagrams, system diagrams, and flowcharts that relate to element grouping for a RIS.

FIG. 1 illustrates an example of a wireless communications system 100 that supports element grouping for a RIS in accordance with one or more aspects of the present disclosure. The wireless communications system 100 may include one or more network entities 105, one or more UEs 115, and a core network 130. In some examples, the wireless communications system 100 may be a Long Term Evolution (LTE) network, an LTE-Advanced (LTE-A) network, an LTE-A Pro network, a New Radio (NR) network, or a network operating in accordance with other systems and radio technologies, including future systems and radio technologies not explicitly mentioned herein.

The network entities 105 may be dispersed throughout a geographic area to form the wireless communications system 100 and may include devices in different forms or having different capabilities. In various examples, a network entity 105 may be referred to as a network element, a mobility element, a radio access network (RAN) node, or network equipment, among other nomenclature. In some examples, network entities 105 and UEs 115 may wirelessly communicate via one or more communication links 125 (e.g., a radio frequency (RF) access link) . For example, a network entity 105 may support a coverage area 110 (e.g., a geographic coverage area) over which the UEs 115 and the network entity 105 may establish one or more communication links 125. The coverage area 110 may be an example of a geographic area over which a network entity 105 and a UE 115 may support the communication of signals according to one or more radio access technologies (RATs) .

The UEs 115 may be dispersed throughout a coverage area 110 of the wireless communications system 100, and each UE 115 may be stationary, or mobile, or both at different times. The UEs 115 may be devices in different forms or having different capabilities. Some example UEs 115 are illustrated in FIG. 1. The UEs 115 described herein may be capable of supporting communications with various types of devices, such as other UEs 115 or network entities 105, as shown in FIG. 1.

As described herein, a node of the wireless communications system 100, which may be referred to as a network node, or a wireless node, may be a network entity 105 (e.g., any network entity described herein) , a UE 115 (e.g., any UE described herein) , a network controller, an apparatus, a device, a computing system, one or more components, or another suitable processing entity configured to perform any of the techniques described herein. For example, a node may be a UE 115. As another example, a node may be a network entity 105. As another example, a first node may be configured to communicate with a second node or a third node. In one aspect of this example, the first node may be a UE 115, the second node may be a network entity 105, and the third node may be a UE 115. In another aspect of this example, the first node may be a UE 115, the second node may be a network entity 105, and the third node may be a network entity 105. In yet other aspects of this example, the first, second, and third nodes may be different relative to these examples. Similarly, reference to a UE 115, network entity 105, apparatus, device, computing system, or the like may include disclosure of the UE 115, network entity 105, apparatus, device, computing system, or the like being a node. For example, disclosure that a UE 115 is configured to receive information from a network entity 105 also discloses that a first node is configured to receive information from a second node.

In some examples, network entities 105 may communicate with the core network 130, or with one another, or both. For example, network entities 105 may communicate with the core network 130 via one or more backhaul communication links 120 (e.g., in accordance with an S1, N2, N3, or other interface protocol) . In some examples, network entities 105 may communicate with one another via a backhaul communication link 120 (e.g., in accordance with an X2, Xn, or other interface protocol) either directly (e.g., directly between network entities 105) or indirectly (e.g., via a core network 130) . In some examples, network entities 105 may communicate with one another via a midhaul communication link 162 (e.g., in accordance with a midhaul interface protocol) or a fronthaul communication link 168 (e.g., in accordance with a fronthaul interface protocol) , or any combination thereof. The backhaul communication links 120, midhaul communication links 162, or fronthaul communication links 168 may be or include one or more wired links (e.g., an electrical link, an optical fiber link) , one or more wireless links (e.g., a radio link, a wireless optical link) , among other examples or various combinations thereof. A UE 115 may communicate with the core network 130 via a communication link 155.

One or more of the network entities 105 described herein may include or may be referred to as a base station 140 (e.g., a base transceiver station, a radio base station, an NR base station, an access point, a radio transceiver, a NodeB, an eNodeB (eNB) , a next-generation NodeB or a giga-NodeB (either of which may be referred to as a gNB) , a 5G NB, a next-generation eNB (ng-eNB) , a Home NodeB, a Home eNodeB, or other suitable terminology) . In some examples, a network entity 105 (e.g., a base station 140) may be implemented in an aggregated (e.g., monolithic, standalone) base station architecture, which may be configured to utilize a protocol stack that is physically or logically integrated within a single network entity 105 (e.g., a single RAN node, such as a base station 140) .

In some examples, a network entity 105 may be implemented in a disaggregated architecture (e.g., a disaggregated base station architecture, a disaggregated RAN architecture) , which may be configured to utilize a protocol stack that is physically or logically distributed among two or more network entities 105, such as an integrated access backhaul (IAB) network, an open RAN (O-RAN) (e.g., a network configuration sponsored by the O-RAN Alliance) , or a virtualized RAN (vRAN) (e.g., a cloud RAN (C-RAN) ) . For example, a network entity 105 may include one or more of a central unit (CU) 160, a distributed unit (DU) 165, a radio unit (RU) 170, a RAN Intelligent Controller (RIC) 175 (e.g., a Near-Real Time RIC (Near-RT RIC) , a Non-Real Time RIC (Non-RT RIC) ) , a Service Management and Orchestration (SMO) 180 system, or any combination thereof. An RU 170 may also be referred to as a radio head, a smart radio head, a remote radio head (RRH) , a remote radio unit (RRU) , or a transmission reception point (TRP) . One or more components of the network entities 105 in a disaggregated RAN architecture may be co-located, or one or more components of the network entities 105 may be located in distributed locations (e.g., separate physical locations) . In some examples, one or more network entities 105 of a disaggregated RAN architecture may be implemented as virtual units (e.g., a virtual CU (VCU) , a virtual DU (VDU) , a virtual RU (VRU) ) .

The split of functionality between a CU 160, a DU 165, and an RU 170 is flexible and may support different functionalities depending on which functions (e.g., network layer functions, protocol layer functions, baseband functions, RF functions, and any combinations thereof) are performed at a CU 160, a DU 165, or an RU 170. For example, a functional split of a protocol stack may be employed between a CU 160 and a DU 165 such that the CU 160 may support one or more layers of the protocol stack and the DU 165 may support one or more different layers of the protocol stack. In some examples, the CU 160 may host upper protocol layer (e.g., layer 3 (L3) , layer 2 (L2) ) functionality and signaling (e.g., Radio Resource Control (RRC) , service data adaption protocol (SDAP) , Packet Data Convergence Protocol (PDCP) ) . The CU 160 may be connected to one or more DUs 165 or Rus 170, and the one or more DUs 165 or Rus 170 may host lower protocol layers, such as layer 1 (L1) (e.g., physical (PHY) layer) or L2 (e.g., radio link control (RLC) layer, medium access control (MAC) layer) functionality and signaling, and may each be at least partially controlled by the CU 160. Additionally, or alternatively, a functional split of the protocol stack may be employed between a DU 165 and an RU 170 such that the DU 165 may support one or more layers of the protocol stack and the RU 170 may support one or more different layers of the protocol stack. The DU 165 may support one or multiple different cells (e.g., via one or more Rus 170) . In some cases, a functional split between a CU 160 and a DU 165, or between a DU 165 and an RU 170 may be within a protocol layer (e.g., some functions for a protocol layer may be performed by one of a CU 160, a DU 165, or an RU 170, while other functions of the protocol layer are performed by a different one of the CU 160, the DU 165, or the RU 170) . A CU 160 may be functionally split further into CU control plane (CU-CP) and CU user plane (CU-UP) functions. A CU 160 may be connected to one or more DUs 165 via a midhaul communication link 162 (e.g., F1, F1-c, F1-u) , and a DU 165 may be connected to one or more Rus 170 via a fronthaul communication link 168 (e.g., open fronthaul (FH) interface) . In some examples, a midhaul communication link 162 or a fronthaul communication link 168 may be implemented in accordance with an interface (e.g., a channel) between layers of a protocol stack supported by respective network entities 105 that are in communication via such communication links.

In wireless communications systems (e.g., wireless communications system 100) , infrastructure and spectral resources for radio access may support wireless backhaul link capabilities to supplement wired backhaul connections, providing an IAB network architecture (e.g., to a core network 130) . In some cases, in an IAB network, one or more network entities 105 (e.g., IAB nodes 104) may be partially controlled by each other. One or more IAB nodes 104 may be referred to as a donor entity or an IAB donor. One or more DUs 165 or one or more Rus 170 may be partially controlled by one or more CUs 160 associated with a donor network entity 105 (e.g., a donor base station 140) . The one or more donor network entities 105 (e.g., IAB donors) may be in communication with one or more additional network entities 105 (e.g., IAB nodes 104) via supported access and backhaul links (e.g., backhaul communication links 120) . IAB nodes 104 may include an IAB mobile termination (IAB-MT) controlled (e.g., scheduled) by DUs 165 of a coupled IAB donor. An IAB-MT may include an independent set of antennas for relay of communications with UEs 115, or may share the same antennas (e.g., of an RU 170) of an IAB node 104 used for access via the DU 165 of the IAB node 104 (e.g., referred to as virtual IAB-MT (vIAB-MT) ) . In some examples, the IAB nodes 104 may include DUs 165 that support communication links with additional entities (e.g., IAB nodes 104, UEs 115) within the relay chain or configuration of the access network (e.g., downstream) . In such cases, one or more components of the disaggregated RAN architecture (e.g., one or more IAB nodes 104 or components of IAB nodes 104) may be configured to operate according to the techniques described herein.

In the case of the techniques described herein applied in the context of a disaggregated RAN architecture, one or more components of the disaggregated RAN architecture may be configured to support element grouping for a RIS as described herein. For example, some operations described as being performed by a UE 115 or a network entity 105 (e.g., a base station 140) may additionally, or alternatively, be performed by one or more components of the disaggregated RAN architecture (e.g., IAB nodes 104, DUs 165, CUs 160, Rus 170, RIC 175, SMO 180) .

A UE 115 may include or may be referred to as a mobile device, a wireless device, a remote device, a handheld device, or a subscriber device, or some other suitable terminology, where the “device” may also be referred to as a unit, a station, a terminal, or a client, among other examples. A UE 115 may also include or may be referred to as a personal electronic device such as a cellular phone, a personal digital assistant (PDA) , a tablet computer, a laptop computer, or a personal computer. In some examples, a UE 115 may include or be referred to as a wireless local loop (WLL) station, an Internet of Things (IoT) device, an Internet of Everything (IoE) device, or a machine type communications (MTC) device, among other examples, which may be implemented in various objects such as appliances, or vehicles, meters, among other examples.

The UEs 115 described herein may be able to communicate with various types of devices, such as other UEs 115 that may sometimes act as relays as well as the network entities 105 and the network equipment including macro eNBs or gNBs, small cell eNBs or gNBs, or relay base stations, among other examples, as shown in FIG. 1.

The UEs 115 and the network entities 105 may wirelessly communicate with one another via one or more communication links 125 (e.g., an access link) using resources associated with one or more carriers. The term “carrier” may refer to a set of RF spectrum resources having a defined physical layer structure for supporting the communication links 125. For example, a carrier used for a communication link 125 may include a portion of a RF spectrum band (e.g., a bandwidth part (BWP) ) that is operated according to one or more physical layer channels for a given radio access technology (e.g., LTE, LTE-A, LTE-A Pro, NR) . Each physical layer channel may carry acquisition signaling (e.g., synchronization signals, system information) , control signaling that coordinates operation for the carrier, user data, or other signaling. The wireless communications system 100 may support communication with a UE 115 using carrier aggregation or multi-carrier operation. A UE 115 may be configured with multiple downlink component carriers and one or more uplink component carriers according to a carrier aggregation configuration. Carrier aggregation may be used with both frequency division duplexing (FDD) and time division duplexing (TDD) component carriers. Communication between a network entity 105 and other devices may refer to communication between the devices and any portion (e.g., entity, sub-entity) of a network entity 105. For example, the terms “transmitting, ” “receiving, ” or “communicating, ” when referring to a network entity 105, may refer to any portion of a network entity 105 (e.g., a base station 140, a CU 160, a DU 165, a RU 170) of a RAN communicating with another device (e.g., directly or via one or more other network entities 105) .

In some examples, such as in a carrier aggregation configuration, a carrier may also have acquisition signaling or control signaling that coordinates operations for other carriers. A carrier may be associated with a frequency channel (e.g., an evolved universal mobile telecommunication system terrestrial radio access (E-UTRA) absolute RF channel number (EARFCN) ) and may be identified according to a channel raster for discovery by the UEs 115. A carrier may be operated in a standalone mode, in which case initial acquisition and connection may be conducted by the UEs 115 via the carrier, or the carrier may be operated in a non-standalone mode, in which case a connection is anchored using a different carrier (e.g., of the same or a different radio access technology) .

The communication links 125 shown in the wireless communications system 100 may include downlink transmissions (e.g., forward link transmissions) from a network entity 105 to a UE 115, uplink transmissions (e.g., return link transmissions) from a UE 115 to a network entity 105, or both, among other configurations of transmissions. Carriers may carry downlink or uplink communications (e.g., in an FDD mode) or may be configured to carry downlink and uplink communications (e.g., in a TDD mode) .

A carrier may be associated with a particular bandwidth of the RF spectrum and, in some examples, the carrier bandwidth may be referred to as a “system bandwidth” of the carrier or the wireless communications system 100. For example, the carrier bandwidth may be one of a set of bandwidths for carriers of a particular radio access technology (e.g., 1.4, 3, 5, 10, 15, 20, 40, or 80 megahertz (MHz) ) . Devices of the wireless communications system 100 (e.g., the network entities 105, the UEs 115, or both) may have hardware configurations that support communications using a particular carrier bandwidth or may be configurable to support communications using one of a set of carrier bandwidths. In some examples, the wireless communications system 100 may include network entities 105 or UEs 115 that support concurrent communications using carriers associated with multiple carrier bandwidths. In some examples, each served UE 115 may be configured for operating using portions (e.g., a sub-band, a BWP) or all of a carrier bandwidth.

Signal waveforms transmitted via a carrier may be made up of multiple subcarriers (e.g., using multi-carrier modulation (MCM) techniques such as orthogonal frequency division multiplexing (OFDM) or discrete Fourier transform spread OFDM (DFT-S-OFDM) ) . In a system employing MCM techniques, a resource element may refer to resources of one symbol period (e.g., a duration of one modulation symbol) and one subcarrier, in which case the symbol period and subcarrier spacing may be inversely related. The quantity of bits carried by each resource element may depend on the modulation scheme (e.g., the order of the modulation scheme, the coding rate of the modulation scheme, or both) , such that a relatively higher quantity of resource elements (e.g., in a transmission duration) and a relatively higher order of a modulation scheme may correspond to a relatively higher rate of communication. A wireless communications resource may refer to a combination of an RF spectrum resource, a time resource, and a spatial resource (e.g., a spatial layer, a beam) , and the use of multiple spatial resources may increase the data rate or data integrity for communications with a UE 115.

One or more numerologies for a carrier may be supported, and a numerology may include a subcarrier spacing (Δf) and a cyclic prefix. A carrier may be divided into one or more BWPs having the same or different numerologies. In some examples, a UE 115 may be configured with multiple BWPs. In some examples, a single BWP for a carrier may be active at a given time and communications for the UE 115 may be restricted to one or more active BWPs.

The time intervals for the network entities 105 or the UEs 115 may be expressed in multiples of a basic time unit which may, for example, refer to a sampling period of T_s=1/ (Δf_max·N_f) seconds, for which Δf_max may represent a supported subcarrier spacing, and N_f may represent a supported discrete Fourier transform (DFT) size. Time intervals of a communications resource may be organized according to radio frames each having a specified duration (e.g., 10 milliseconds (ms) ) . Each radio frame may be identified by a system frame number (SFN) (e.g., ranging from 0 to 1023) .

Each frame may include multiple consecutively-numbered subframes or slots, and each subframe or slot may have the same duration. In some examples, a frame may be divided (e.g., in the time domain) into subframes, and each subframe may be further divided into a quantity of slots. Alternatively, each frame may include a variable quantity of slots, and the quantity of slots may depend on subcarrier spacing. Each slot may include a quantity of symbol periods (e.g., depending on the length of the cyclic prefix prepended to each symbol period) . In some wireless communications systems 100, a slot may further be divided into multiple mini-slots associated with one or more symbols. Excluding the cyclic prefix, each symbol period may be associated with one or more (e.g., N_f) sampling periods. The duration of a symbol period may depend on the subcarrier spacing or frequency band of operation.

A subframe, a slot, a mini-slot, or a symbol may be the smallest scheduling unit (e.g., in the time domain) of the wireless communications system 100 and may be referred to as a transmission time interval (TTI) . In some examples, the TTI duration (e.g., a quantity of symbol periods in a TTI) may be variable. Additionally, or alternatively, the smallest scheduling unit of the wireless communications system 100 may be dynamically selected (e.g., in bursts of shortened TTIs (sTTIs) ) .

Physical channels may be multiplexed for communication using a carrier according to various techniques. A physical control channel and a physical data channel may be multiplexed for signaling via a downlink carrier, for example, using one or more of time division multiplexing (TDM) techniques, frequency division multiplexing (FDM) techniques, or hybrid TDM-FDM techniques. A control region (e.g., a control resource set (CORESET) ) for a physical control channel may be defined by a set of symbol periods and may extend across the system bandwidth or a subset of the system bandwidth of the carrier. One or more control regions (e.g., CORESETs) may be configured for a set of the UEs 115. For example, one or more of the UEs 115 may monitor or search control regions for control information according to one or more search space sets, and each search space set may include one or multiple control channel candidates in one or more aggregation levels arranged in a cascaded manner. An aggregation level for a control channel candidate may refer to an amount of control channel resources (e.g., control channel elements (CCEs) ) associated with encoded information for a control information format having a given payload size. Search space sets may include common search space sets configured for sending control information to multiple UEs 115 and UE-specific search space sets for sending control information to a specific UE 115.

A network entity 105 may provide communication coverage via one or more cells, for example a macro cell, a small cell, a hot spot, or other types of cells, or any combination thereof. The term “cell” may refer to a logical communication entity used for communication with a network entity 105 (e.g., using a carrier) and may be associated with an identifier for distinguishing neighboring cells (e.g., a physical cell identifier (PCID) , a virtual cell identifier (VCID) , or others) . In some examples, a cell also may refer to a coverage area 110 or a portion of a coverage area 110 (e.g., a sector) over which the logical communication entity operates. Such cells may range from smaller areas (e.g., a structure, a subset of structure) to larger areas depending on various factors such as the capabilities of the network entity 105. For example, a cell may be or include a building, a subset of a building, or exterior spaces between or overlapping with coverage areas 110, among other examples.

A macro cell generally covers a relatively large geographic area (e.g., several kilometers in radius) and may allow unrestricted access by the UEs 115 with service subscriptions with the network provider supporting the macro cell. A small cell may be associated with a lower-powered network entity 105 (e.g., a lower-powered base station 140) , as compared with a macro cell, and a small cell may operate using the same or different (e.g., licensed, unlicensed) frequency bands as macro cells. Small cells may provide unrestricted access to the UEs 115 with service subscriptions with the network provider or may provide restricted access to the UEs 115 having an association with the small cell (e.g., the UEs 115 in a closed subscriber group (CSG) , the UEs 115 associated with users in a home or office) . A network entity 105 may support one or multiple cells and may also support communications via the one or more cells using one or multiple component carriers.

In some examples, a carrier may support multiple cells, and different cells may be configured according to different protocol types (e.g., MTC, narrowband IoT (NB-IoT) , enhanced mobile broadband (eMBB) ) that may provide access for different types of devices.

In some examples, a network entity 105 (e.g., a base station 140, an RU 170) may be movable and therefore provide communication coverage for a moving coverage area 110. In some examples, different coverage areas 110 associated with different technologies may overlap, but the different coverage areas 110 may be supported by the same network entity 105. In some other examples, the overlapping coverage areas 110 associated with different technologies may be supported by different network entities 105. The wireless communications system 100 may include, for example, a heterogeneous network in which different types of the network entities 105 provide coverage for various coverage areas 110 using the same or different radio access technologies.

The wireless communications system 100 may support synchronous or asynchronous operation. For synchronous operation, network entities 105 (e.g., base stations 140) may have similar frame timings, and transmissions from different network entities 105 may be approximately aligned in time. For asynchronous operation, network entities 105 may have different frame timings, and transmissions from different network entities 105 may, in some examples, not be aligned in time. The techniques described herein may be used for either synchronous or asynchronous operations.

Some UEs 115, such as MTC or IoT devices, may be low cost or low complexity devices and may provide for automated communication between machines (e.g., via Machine-to-Machine (M2M) communication) . M2M communication or MTC may refer to data communication technologies that allow devices to communicate with one another or a network entity 105 (e.g., a base station 140) without human intervention. In some examples, M2M communication or MTC may include communications from devices that integrate sensors or meters to measure or capture information and relay such information to a central server or application program that uses the information or presents the information to humans interacting with the application program. Some UEs 115 may be designed to collect information or enable automated behavior of machines or other devices. Examples of applications for MTC devices include smart metering, inventory monitoring, water level monitoring, equipment monitoring, healthcare monitoring, wildlife monitoring, weather and geological event monitoring, fleet management and tracking, remote security sensing, physical access control, and transaction-based business charging.

Some UEs 115 may be configured to employ operating modes that reduce power consumption, such as half-duplex communications (e.g., a mode that supports one-way communication via transmission or reception, but not transmission and reception concurrently) . In some examples, half-duplex communications may be performed at a reduced peak rate. Other power conservation techniques for the UEs 115 include entering a power saving deep sleep mode when not engaging in active communications, operating using a limited bandwidth (e.g., according to narrowband communications) , or a combination of these techniques. For example, some UEs 115 may be configured for operation using a narrowband protocol type that is associated with a defined portion or range (e.g., set of subcarriers or resource blocks (RBs) ) within a carrier, within a guard-band of a carrier, or outside of a carrier.

The wireless communications system 100 may be configured to support ultra-reliable communications or low-latency communications, or various combinations thereof. For example, the wireless communications system 100 may be configured to support ultra-reliable low-latency communications (URLLC) . The UEs 115 may be designed to support ultra-reliable, low-latency, or critical functions. Ultra-reliable communications may include private communication or group communication and may be supported by one or more services such as push-to-talk, video, or data. Support for ultra-reliable, low-latency functions may include prioritization of services, and such services may be used for public safety or general commercial applications. The terms ultra-reliable, low-latency, and ultra-reliable low-latency may be used interchangeably herein.

In some examples, a UE 115 may be configured to support communicating directly with other UEs 115 via a device-to-device (D2D) communication link 135 (e.g., in accordance with a peer-to-peer (P2P) , D2D, or sidelink protocol) . In some examples, one or more UEs 115 of a group that are performing D2D communications may be within the coverage area 110 of a network entity 105 (e.g., a base station 140, an RU 170) , which may support aspects of such D2D communications being configured by (e.g., scheduled by) the network entity 105. In some examples, one or more UEs 115 of such a group may be outside the coverage area 110 of a network entity 105 or may be otherwise unable to or not configured to receive transmissions from a network entity 105. In some examples, groups of the UEs 115 communicating via D2D communications may support a one-to-many (1: M) system in which each UE 115 transmits to each of the other UEs 115 in the group. In some examples, a network entity 105 may facilitate the scheduling of resources for D2D communications. In some other examples, D2D communications may be carried out between the UEs 115 without an involvement of a network entity 105.

In some systems, a D2D communication link 135 may be an example of a communication channel, such as a sidelink communication channel, between vehicles (e.g., UEs 115) . In some examples, vehicles may communicate using vehicle-to-everything (V2X) communications, vehicle-to-vehicle (V2V) communications, or some combination of these. A vehicle may signal information related to traffic conditions, signal scheduling, weather, safety, emergencies, or any other information relevant to a V2X system. In some examples, vehicles in a V2X system may communicate with roadside infrastructure, such as roadside units, or with the network via one or more network nodes (e.g., network entities 105, base stations 140, Rus 170) using vehicle-to-network (V2N) communications, or with both.

The core network 130 may provide user authentication, access authorization, tracking, Internet Protocol (IP) connectivity, and other access, routing, or mobility functions. The core network 130 may be an evolved packet core (EPC) or 5G core (5GC) , which may include at least one control plane entity that manages access and mobility (e.g., a mobility management entity (MME) , an access and mobility management function (AMF) ) and at least one user plane entity that routes packets or interconnects to external networks (e.g., a serving gateway (S-GW) , a Packet Data Network (PDN) gateway (P-GW) , or a user plane function (UPF) ) . The control plane entity may manage non-access stratum (NAS) functions such as mobility, authentication, and bearer management for the UEs 115 served by the network entities 105 (e.g., base stations 140) associated with the core network 130. User IP packets may be transferred through the user plane entity, which may provide IP address allocation as well as other functions. The user plane entity may be connected to IP services 150 for one or more network operators. The IP services 150 may include access to the Internet, Intranet (s) , an IP Multimedia Subsystem (IMS) , or a Packet-Switched Streaming Service.

The wireless communications system 100 may operate using one or more frequency bands, which may be in the range of 300 megahertz (MHz) to 300 gigahertz (GHz) . Generally, the region from 300 MHz to 3 GHz is known as the ultra-high frequency (UHF) region or decimeter band because the wavelengths range from approximately one decimeter to one meter in length. UHF waves may be blocked or redirected by buildings and environmental features, which may be referred to as clusters, but the waves may penetrate structures sufficiently for a macro cell to provide service to the UEs 115 located indoors. Communications using UHF waves may be associated with smaller antennas and shorter ranges (e.g., less than 100 kilometers) compared to communications using the smaller frequencies and longer waves of the high frequency (HF) or very high frequency (VHF) portion of the spectrum below 300 MHz.

The wireless communications system 100 may also operate using a super high frequency (SHF) region, which may be in the range of 3 GHz to 30 GHz, also known as the centimeter band, or using an extremely high frequency (EHF) region of the spectrum (e.g., from 30 GHz to 300 GHz) , also known as the millimeter band. In some examples, the wireless communications system 100 may support millimeter wave (mmW) communications between the UEs 115 and the network entities 105 (e.g., base stations 140, Rus 170) , and EHF antennas of the respective devices may be smaller and more closely spaced than UHF antennas. In some examples, such techniques may facilitate using antenna arrays within a device. The propagation of EHF transmissions, however, may be subject to even greater attenuation and shorter range than SHF or UHF transmissions. The techniques disclosed herein may be employed across transmissions that use one or more different frequency regions, and designated use of bands across these frequency regions may differ by country or regulating body.

The wireless communications system 100 may utilize both licensed and unlicensed RF spectrum bands. For example, the wireless communications system 100 may employ License Assisted Access (LAA) , LTE-Unlicensed (LTE-U) radio access technology, or NR technology using an unlicensed band such as the 5 GHz industrial, scientific, and medical (ISM) band. While operating using unlicensed RF spectrum bands, devices such as the network entities 105 and the UEs 115 may employ carrier sensing for collision detection and avoidance. In some examples, operations using unlicensed bands may be based on a carrier aggregation configuration in conjunction with component carriers operating using a licensed band (e.g., LAA) . Operations using unlicensed spectrum may include downlink transmissions, uplink transmissions, P2P transmissions, or D2D transmissions, among other examples.

A network entity 105 (e.g., a base station 140, an RU 170) or a UE 115 may be equipped with multiple antennas, which may be used to employ techniques such as transmit diversity, receive diversity, multiple-input multiple-output (MIMO) communications, or beamforming. The antennas of a network entity 105 or a UE 115 may be located within one or more antenna arrays or antenna panels, which may support MIMO operations or transmit or receive beamforming. For example, one or more base station antennas or antenna arrays may be co-located at an antenna assembly, such as an antenna tower. In some examples, antennas or antenna arrays associated with a network entity 105 may be located at diverse geographic locations. A network entity 105 may include an antenna array with a set of rows and columns of antenna ports that the network entity 105 may use to support beamforming of communications with a UE 115. Likewise, a UE 115 may include one or more antenna arrays that may support various MIMO or beamforming operations. Additionally, or alternatively, an antenna panel may support RF beamforming for a signal transmitted via an antenna port.

The network entities 105 or the UEs 115 may use MIMO communications to exploit multipath signal propagation and increase spectral efficiency by transmitting or receiving multiple signals via different spatial layers. Such techniques may be referred to as spatial multiplexing. The multiple signals may, for example, be transmitted by the transmitting device via different antennas or different combinations of antennas. Likewise, the multiple signals may be received by the receiving device via different antennas or different combinations of antennas. Each of the multiple signals may be referred to as a separate spatial stream and may carry information associated with the same data stream (e.g., the same codeword) or different data streams (e.g., different codewords) . Different spatial layers may be associated with different antenna ports used for channel measurement and reporting. MIMO techniques include single-user MIMO (SU-MIMO) , for which multiple spatial layers are transmitted to the same receiving device, and multiple-user MIMO (MU-MIMO) , for which multiple spatial layers are transmitted to multiple devices.

Beamforming, which may also be referred to as spatial filtering, directional transmission, or directional reception, is a signal processing technique that may be used at a transmitting device or a receiving device (e.g., a network entity 105, a UE 115) to shape or steer an antenna beam (e.g., a transmit beam, a receive beam) along a spatial path between the transmitting device and the receiving device. Beamforming may be achieved by combining the signals communicated via antenna elements of an antenna array such that some signals propagating along particular orientations with respect to an antenna array experience constructive interference while others experience destructive interference. The adjustment of signals communicated via the antenna elements may include a transmitting device or a receiving device applying amplitude offsets, phase offsets, or both to signals carried via the antenna elements associated with the device. The adjustments associated with each of the antenna elements may be defined by a beamforming weight set associated with a particular orientation (e.g., with respect to the antenna array of the transmitting device or receiving device, or with respect to some other orientation) .

A network entity 105 or a UE 115 may use beam sweeping techniques as part of beamforming operations. For example, a network entity 105 (e.g., a base station 140, an RU 170) may use multiple antennas or antenna arrays (e.g., antenna panels) to conduct beamforming operations for directional communications with a UE 115. Some signals (e.g., synchronization signals, reference signals, beam selection signals, or other control signals) may be transmitted by a network entity 105 multiple times along different directions. For example, the network entity 105 may transmit a signal according to different beamforming weight sets associated with different directions of transmission. Transmissions along different beam directions may be used to identify (e.g., by a transmitting device, such as a network entity 105, or by a receiving device, such as a UE 115) a beam direction for later transmission or reception by the network entity 105.

Some signals, such as data signals associated with a particular receiving device, may be transmitted by transmitting device (e.g., a transmitting network entity 105, a transmitting UE 115) along a single beam direction (e.g., a direction associated with the receiving device, such as a receiving network entity 105 or a receiving UE 115) . In some examples, the beam direction associated with transmissions along a single beam direction may be determined based on a signal that was transmitted along one or more beam directions. For example, a UE 115 may receive one or more of the signals transmitted by the network entity 105 along different directions and may report to the network entity 105 an indication of the signal that the UE 115 received with a highest signal quality or an otherwise acceptable signal quality.

In some examples, transmissions by a device (e.g., by a network entity 105 or a UE 115) may be performed using multiple beam directions, and the device may use a combination of digital precoding or beamforming to generate a combined beam for transmission (e.g., from a network entity 105 to a UE 115) . The UE 115 may report feedback that indicates precoding weights for one or more beam directions, and the feedback may correspond to a configured set of beams across a system bandwidth or one or more sub-bands. The network entity 105 may transmit a reference signal (e.g., a cell-specific reference signal (CRS) , a CSI reference signal (CSI-RS) ) , which may be precoded or unprecoded. The UE 115 may provide feedback for beam selection, which may be a precoding matrix indicator (PMI) or codebook-based feedback (e.g., a multi- panel type codebook, a linear combination type codebook, a port selection type codebook) . Although these techniques are described with reference to signals transmitted along one or more directions by a network entity 105 (e.g., a base station 140, an RU 170) , a UE 115 may employ similar techniques for transmitting signals multiple times along different directions (e.g., for identifying a beam direction for subsequent transmission or reception by the UE 115) or for transmitting a signal along a single direction (e.g., for transmitting data to a receiving device) .

A receiving device (e.g., a UE 115) may perform reception operations in accordance with multiple receive configurations (e.g., directional listening) when receiving various signals from a receiving device (e.g., a network entity 105) , such as synchronization signals, reference signals, beam selection signals, or other control signals. For example, a receiving device may perform reception in accordance with multiple receive directions by receiving via different antenna subarrays, by processing received signals according to different antenna subarrays, by receiving according to different receive beamforming weight sets (e.g., different directional listening weight sets) applied to signals received at multiple antenna elements of an antenna array, or by processing received signals according to different receive beamforming weight sets applied to signals received at multiple antenna elements of an antenna array, any of which may be referred to as “listening” according to different receive configurations or receive directions. In some examples, a receiving device may use a single receive configuration to receive along a single beam direction (e.g., when receiving a data signal) . The single receive configuration may be aligned along a beam direction determined based on listening according to different receive configuration directions (e.g., a beam direction determined to have a highest signal strength, highest signal-to-noise ratio (SNR) , or otherwise acceptable signal quality based on listening according to multiple beam directions) .

The wireless communications system 100 may be a packet-based network that operates according to a layered protocol stack. In the user plane, communications at the bearer or PDCP layer may be IP-based. An RLC layer may perform packet segmentation and reassembly to communicate via logical channels. A MAC layer may perform priority handling and multiplexing of logical channels into transport channels. The MAC layer also may implement error detection techniques, error correction techniques, or both to support retransmissions to improve link efficiency. In the control plane, an RRC layer may provide establishment, configuration, and maintenance of an RRC connection between a UE 115 and a network entity 105 or a core network 130 supporting radio bearers for user plane data. A PHY layer may map transport channels to physical channels.

The UEs 115 and the network entities 105 may support retransmissions of data to increase the likelihood that data is received successfully. Hybrid automatic repeat request (HARQ) feedback is one technique for increasing the likelihood that data is received correctly via a communication link (e.g., a communication link 125, a D2D communication link 135) . HARQ may include a combination of error detection (e.g., using a cyclic redundancy check (CRC) ) , forward error correction (FEC) , and retransmission (e.g., automatic repeat request (ARQ) ) . HARQ may improve throughput at the MAC layer in poor radio conditions (e.g., low signal-to-noise conditions) . In some examples, a device may support same-slot HARQ feedback, in which case the device may provide HARQ feedback in a specific slot for data received via a previous symbol in the slot. In some other examples, the device may provide HARQ feedback in a subsequent slot, or according to some other time interval.

In some examples, the wireless communications system 100 may include a RIS that is operable to reflect communications between a network entity 105 and a UE 115. The RIS may support one or more RIS element grouping capabilities to reflect wireless communication signals, and may transmit a capability message to the network entity 105 to indicate supported RIS element grouping types. The network entity 105 may determine a RIS element grouping type for the RIS to use during a set of resources based on the capability message and one or more available radio resources. The network entity 105 may transmit a grouping message to indicate the selected element grouping type and the set of resources to the RIS and the UE 115, and may transmit one or more signals for reflection during the set of resources.

The UE 115 may receive the grouping message and the one or more signals (e.g., at least partially reflected signals) and may perform channel estimation based on measurements of the one or more signals and the grouping message. The UE 115 may determine a set of reflection coefficients based on the measurements, where each reflection coefficient may correspond to a respective RIS element group. The UE 115 may transmit a report (e.g., CSI report) to the network entity 105 that includes the set of reflection coefficients. The network entity 105 may forward the reflection coefficients to the RIS to use in subsequent operations.

FIG. 2 illustrates an example of a wireless communications system 200 that supports element grouping for a RIS in accordance with aspects of the present disclosure. In some examples, the wireless communications system 200 may implement aspects of the wireless communications system 100 or may be implemented by aspects of the wireless communications system 100. For example, the wireless communications system 200 may include a network entity 105-a and a UE 115-a, which may represent examples of a network entity 105 and a UE 115 as described with reference to FIG. 1. The network entity 105-a may communicate with the UE 115-a within a geographic coverage area 110-a and via one or more communication links. The wireless communications system 200 may utilize one or more capability messages 225, one or more grouping messages 230, one or more reports 235, or any combination thereof to improve channel estimation methods according to techniques described herein.

The network entity 105-a and the UE 115-a may perform wireless communications using a RIS 205. The RIS 205 may include a quantity of reconfigurable elements 245 (e.g., cells, unit cells, scattering units, RIS elements, antenna elements, meta-elements, or other reflective, electrically-controllable elements) that are operable to redirect wireless communications. In some examples, the RIS 205 may include a controller 240 (e.g., one or more processors with associated memory) that may support communications with the network entity 105-a, the UE 115-a, or both. Additionally, or alternatively, the RIS 205 may perform reflection or refraction of wireless communications without a controller 240. In some cases, the RIS 205 may receive signaling from the network entity 105-a (e.g., using the RIS controller 240) to configure each of the elements 245 to redirect wireless communication in desired directions. For example, the RIS 205 may reflect communications (e.g., reflective only RIS) , or may refract communications (e.g., transmissive RIS) , or both (e.g., simultaneously transmitting and reflecting (STAR) RIS, hybrid-RIS, omni-RIS) to avoid obstacles, such as the blockage 220, between the UE 115-a and the network entity 105-a or otherwise improve communication quality. Deployment of the RIS 205 may be associated with a relatively low cost (e.g., due to the RIS 205 being) and a relatively low power consumption for the wireless communications system 200. For example, the RIS 205 may be composed with positive intrinsic negative (PIN) diodes, or varactor diodes, or other hardware components associated with a relatively low cost. Additionally, or alternatively, the RIS 205 may consume a relatively small amount of control power and may not consume radiation power, which may reduce power consumption.

In some cases, the RIS 205 may perform reflective beamforming for communications between the network entity 105-a and the UE 115-a. Such reflective beamforming communications may be associated with a reflection gain by the RIS 205. The reflection gain may be determined according to one or more models. For example, a general model may apply when the network entity 105-a and the UE 115-a are in the near field or far field of the RIS 205. The reflection beamforming gain by the RIS 205 for an incident angle {θ_i, n} and a reflection angle {θ_r, n} in the general model may be represented by Equation 1.

In the example of Equation 1, d_i, n may denote a distance between the transmitter and a RIS element n, and d_r, n may likewise denote a distance between the receiver and the RIS element n. Further, may represent a reflection coefficient for the RIS element n, where α_n may denote the amplitude of the reflection coefficient and φ_n may denote the phase of the reflection coefficient. Additionally, or alternatively, a far-field model may apply when the network entity 105-a and the UE 115-a are in the far field of the RIS 205. In such examples, the equation to determine the reflection beamforming gain may be simplified from Equation 1 and rewritten as Equation 2 below.

In Equation 2, d may be the distance between individual RIS elements, and the reflection gain by the RIS 205 may be based on an incident angle θ_i and a reflected angle θ_r. The wireless communications system 200 may include one or more communication links. For example, the network entity 105-a and the UE 115-a may communicate via a direct link 215. However, in some cases, a blockage 220 (e.g., building, tree, or some other obstruction) may prevent or inhibit communications via the direct link 215. In such cases, the network entity 105-a and the UE 115-a may use the RIS 205 to communicate via a reflection link 210 (e.g., including communication links 210-a and 210-b) instead of the direct link 215. Additionally, or alternatively, the blockage 220 may not be present or may otherwise not prevent the direct link 215, and both the reflection link 210 and the direct link 215 may exist together (e.g., simultaneously) between the network entity 105-a and the UE 115-a.

The UE 115-a may model a signal received from the network entity 105-abased on the links between the UE 115-a and the network entity 105-a (e.g., the reflection link 210, the direct link 215, or both) and the antennas used to transmit the signal. In some cases, the model may represent a precoding matrix (e.g., beamforming weights, beamforming coefficients) applied by the network entity 105 as W_g, a RIS element 245 reflection coefficient as w_r, the communication link 210-a as H_gr, the communication link 210-b as H_ru, and the direct link 215 as H_gu. For example, in cases where the network entity 105-a and the UE 115-a communicate via the reflection link 210 and refrain from communicating via the direct link 215, and the network entity 105-a transmits a signal from one antenna m, the UE 115-a may model the received signal with the equation y_m=H_ru·Diag (w_r) ·H_gr (: , m) x+noise. Using the definitionand further simplifying, the equation for the received signal y_m may be rewritten as Equation 3 below.

y_m=A_mw_rx+noise (3)

Similarly, in cases where the network entity 105-a and the UE 115-a communicate via the reflection link 210 and refrain from communicating via the direct link 215, and the network entity 105-a transmits a precoded signal from all transmit antennas, the UE 115-a may model the received signal with the equation y=H_ru· Diag (w_r) ·H_gr·W_gx+noise. Using the definition for A_m above and further simplifying, the equation for the received signal y may be rewritten as Equation 4 below.

Additionally, or alternatively, in cases where the network entity 105-a and the UE 115-a communicate via both a reflection link 210 and a direct link 215 and the network entity 105-a transmits a signal from one antenna m, the UE 115-a may model the received signal with the equation y_m= (H_gu (: , m) +H_ru·Diag (w_r) ·H_gr (: , m) ) x+noise. Using the definitionsand and further simplifying, the equation for the received signal y_m may be rewritten as Equation 5 below.

Similarly, in cases where the network entity 105-a and the UE 115-a communicate via both the reflection link 210 and the direct link 215 and the network entity 105-a transmits a precoded signal from all antennas, the UE 115-a may model the received signal with the equation y= (H_gu+H_ru·Diag (w_r) ·H_gr) ·W_gx+noise. Using the definition forabove and further simplifying, the equation for the received signal y may be rewritten as Equation 6 below.

The wireless communications system 200 may support one or more channel estimation methods to perform channel estimation while accounting for the reflection link 210. For example, the wireless communications system 200 may support per-element on-off, LS, CS, or some other method for channel estimation. In some examples, the network entity 105-a may select a channel estimation method and may indicate the selected channel estimation method to the UE 115-a, the RIS 205, or both. The UE 115-a may use the indicated channel estimation method to estimate the reflection link 210, the direct link 215, or both.

In some cases, when the network entity 105-a transmits a signal with an antenna m, a quantity of measurements, T, may be made with different reflection coefficients w_r, _t. For example, a UE 115-a may calculate multiple measurements using y_m, t=A_mw_r, tx_t+noise, where t=1～T. Applying a definition that for the antenna m, an aggregated measured channel may be modeled by Equation 7 below.

In some cases, if the network entity 105-a indicates that the UE 115-a is to use the per element on-off method to perform channel estimation, the RIS 205 may switch each RIS element 245 on or off individually. For example, the system may configure the RIS 205 to switch a single element 245 on and the remaining elements off at a given time (e.g., w_r, t= [0, …0, 1, 0, …, 0] ^T) , and the UE 115-a may then derive a corresponding column of A_m. The per element on-off method may be associated with relatively low processing complexity and may apply for various network topologies and conditions (e.g., may be robust) . However, per element on-off may also be associated with relatively low signal strength (e.g., due to using a single RIS element 245 at a time) and with relatively high radio resource consumption (e.g., the quantity of measurements may be the same as the quantity of RIS elements 245) . Thus, the wireless communications system 200 may apply per element on-off when the quantity of RIS elements 245 is relatively small, or when the system has relatively small coverage with sufficient receive power using a single RIS element 245.

Additionally, or alternatively, if the network entity 105-a indicates that the UE 115-a is to use the LS method, A_m can be estimated according to Equation 8 below. N_r may represent a quantity of RIS elements 245 in the RIS 205. In the example of Equation 8, the expression rank (B) =N_r may be satisfied to enable matrix inversion operations (e.g., which may imply T≥N_r) . The LS method may also apply for various network topologies and conditions (e.g., robust) and may be associated with a higher receive signal strength than the per element on-off method. However, LS may be associated with a higher processing complexity than per element on-off and may also be associated with relatively high radio resource consumption (e.g., the quantity of measurements may be the same as the quantity of RIS elements 245) . Thus, the wireless communications system 200 may apply LS channel estimation methods when the quantity of RIS elements 245 (e.g., N_r) is relatively small.

Additionally, or alternatively, the network entity 105-a may indicate that the UE 115-a is to use the CS method to perform channel estimation. The CS method may use a sparse channel model to perform measurements in a radio channel with sparse paths. For example, the system may modeland wheremay represent a steering vector with incident directionat the RIS 205, may represent a steering vector with received directionat the UE 115-a, andmay represent a steering vector with reflective directionat the RIS 205. Thus, for a transmit antenna m, the model for A_m=H_ru·Diag (H_gr (: , m) ) may be represented by Equation 9 below.

In the example of Equation 9, may be equivalently written asFurther, there may be KL virtual paths, and each virtual path may correspond to a path pairAs such, a model A_i may be determined according to Equation 10 below.

CS channel estimation methods may be associated with a relatively low radio resource consumption in comparison with per element on-off and LS (e.g., the quantity of measurements may be smaller than the quantity of RIS elements 245) . However, CS methods may be associated with relatively high complexity (e.g., higher complexity than per element on-off) and complexity may further increase in some conditions (e.g., may be non-robust) . For example, to improve reliability of the CS channel estimation method, the UE 115-a may perform multiple measurements with different reflection coefficients w_r, t (e.g., t=1～T) in order to ensure convergency. Accordingly, if a quantity of variables is relatively large, the complexity of the CS method may also be relatively high. Thus, the wireless communications system 200 may apply CS channel estimation methods in a sparse radio channel, or in cases with a relatively small quantity of variables. For example, if the RIS 205 incident direction in the reflection link 210 is known by pre-measurement then A_m may be determined according to Equation 11 below. Additionally, or alternatively, if the network entity 105-a, the RIS 205, and the UE 115-a are all in a horizontal plane (e.g., only 1D direction (θ) is considered) A_m may be determined according to Equation 12 below.

In the wireless communications system 200, the quantity of consumed radio resources (e.g., CSI-RS resources) to perform channel estimation may be the same as or greater than the quantity of elements 245 in the RIS 205. For example, if the RIS 205 has a relatively large quantity of elements 245 (e.g., meta-elements) , the consumption of radio resources may also be relatively high, which may degrade system performance (e.g., increase power consumption, increase processing overhead, increase resource congestion) . In some cases, the RIS 205 may divide all the elements 245 of the RIS 205 into several element groups and may apply a common reflection coefficient to each element 245 in an element group (e.g., each element group may act as one virtual element when reflecting wireless communications) . An increase in element group size may lead to a decrease in a quantity of element groups, which may reduce the radio resource consumption. However, grouping RIS elements 245 into element groups may also reduce RIS reflection beamforming gain.

Further, different types of RISs 205 (e.g., high-end RIS, low-end RIS) may have different capabilities (e.g., based on hardware configurations, hardware cost) for element groupings. For example, each RIS element 245 may be connected with a respective control line or several RIS elements 245 may share a common control line, thus affecting the possible grouping configurations, as described in further detail elsewhere herein, including with reference to FIG. 3. In some cases, the network entity 105-a, or the UE 115-a, or both, may perform channel estimation based on RIS capability information (e.g., RIS element grouping capability) . Thus, an appropriate element group size based on the capability of the RIS 205 and a quantity of available channel estimation radio resources (e.g., CSI-RS resources) may be desired to improve system performance (e.g., obtain satisfactory tradeoff between performance and overhead) .

According to techniques described herein, the wireless communications system 200 may employ techniques (e.g., protocols, signaling messages, and algorithms) to support RIS element grouping based on a capability of the RIS 205 and a quantity of available channel estimation radio resources. In some examples, the RIS 205 may support multiple grouping capabilities or may only support one grouping capability (e.g., due to hardware cost of supporting multiple types) . The RIS 205 may send a capability message 225 to the network entity 105-a that indicates one or more capabilities of the RIS 205 (e.g., element grouping capabilities, hardware capabilities) , a classification of capability (e.g., even element groupings, uneven element groupings) , both, or some other capability information. The capability message 225 may further indicate a quantity of element groups and a quantity of elements 245 in each group.

In some examples, the network entity 105-a may determine one or more element grouping types based on the capability message 225 and a quantity of available channel estimation radio resources. The network entity 105-a may transmit a grouping message 230 to the RIS 205 and the UE 115-a that indicates one or more selected element grouping types and a set of resources allocated for reflection of communications using the one or more selected element grouping types. The network entity 105-a may send a same grouping message 230 to the RIS 205 and the UE 115-a, or may send a first grouping message 230 to the RIS 205 and a second grouping message 230 to the UE 115-a. The network entity 105-a may send the grouping message 230 via the reflection link 210, or the direct link 215, or both. The RIS 205 may receive the grouping message 230 and configure the RIS elements 245 according to the selected grouping type received in the grouping message 230 for reflection of configured radio resources (e.g., channel estimation resources, CSI-RSs) .

In some examples, the UE 115-a may receive the grouping message 230 and perform channel estimation for the reflection link 210 based on an indication in the grouping message 230 (e.g., quantity of RIS element groups or other RIS element grouping information) . For example, the UE 115-a may perform channel estimation measurements on one or more signals and determine a reflection coefficient for each element group as indicated in the grouping message 230. In some examples, the UE 115-a may transmit a report 235 (e.g., CSI report) to the network entity 105-a that includes an indication of each reflection coefficient for each element group. The UE 115-a may transmit the report 235 to the network entity 105-a via the direct link 215, or the reflection link 210, or both. Additionally, or alternatively, the UE 115-a may transmit the report 235 directly to the RIS 205 via a sidelink communication channel. For example, the reflection link 210-b may represent a sidelink communication link between the UE 115-a and the RIS 205, and the UE 115-a may transmit the report 235 via the sidelink communication link in addition to or instead of transmitting the report 235 to the network entity 105-a. In some examples, the network entity 105-a may transmit (e.g., forward) the report 235 to the RIS 205. The RIS 205 may further operate according to information from the report 235 (e.g., reflection coefficient information) during subsequent operations (e.g., control transmissions, physical downlink control channel (PDCCH) , physical uplink control channel (PUCCH) , data transmissions, physical downlink shared channel (PDSCH) , physical uplink shared channel (PUSCH) ) .

FIG. 3 illustrates examples of RIS hardware configurations 300 that support RIS element configuration for channel estimation in accordance with aspects of the present disclosure. The RIS hardware configurations 300 may implement or be implemented by aspects of the wireless communications systems 100 and 200. For example, FIG. 3 illustrates three example RIS hardware configurations 300-a, 300-b, and 300-c for three RISs 305-a, 305-b, and 305-c, respectively. The RISs 305-a, 305-b, and 305-c may represent examples of the RIS 205 described with reference to FIG. 2. Each RIS 305 may include or be coupled with a respective RIS controller 240 and one or more RIS elements 245 (e.g., meta-elements, antenna elements, antenna arrays) , which may represent examples of corresponding devices and components as described with reference to FIG. 2. Each RIS 305 may include or be coupled with one or more control lines 310 and one or more grouping lines 315 which may connect the respective RIS controller 240 to the RIS elements 245. Each RIS hardware configuration 300 represents an example configuration of hardware at the RIS 305 to support one or more capabilities (e.g., group size and group quantity capabilities) for grouping RIS elements 245 into element groups 320 to improve channel estimation methods according to aspects described herein.

The RIS 305-a may support element grouping in accordance with the RIS hardware configuration 300-a. For example, the RIS 305-a may include or be coupled with respective control lines 310 for each element 245 of the RIS 305-a. The RIS 305-a may include, for example, 12 elements 245 and 12 independent control lines 310. Each group line 315 may accordingly connect each element 245 to a respective control line 310. Thus, the RIS 305-a may support a capability for an element group 320-a, which may correspond to a group size of one element 245 per element group 320-a and a quantity of 12 groups. The RIS controller 240-a may control each RIS element 245 independently in accordance with the RIS hardware configuration 300-a.

The RIS 305-b may support element grouping in accordance with the RIS hardware configuration 300-b. In such examples, multiple elements 245 of the RIS 305-b may share a common control line 310. The RIS 305-b may include or be coupled with, for example, twelve (12) elements 245 and four (4) independent control lines 310. Each grouping line 315 may be coupled with a single element 245 of the RIS 305-b, and three (3) grouping lines 315 and corresponding elements 245 may be connected to a single common control line 310 (e.g., a shared control line) . Thus, the RIS 305-b may support a capability for an element group 320-b, which may correspond to a group size of three (3) elements 245 per element group 320-b and a quantity of four (4) groups. The RIS controller 240-b may accordingly control each element group 320-b independently. For example, the RIS controller 240-b may apply a respective beamforming weight or RIS reflection coefficient to each element group 320-b, such that each element group 320-b may operate as a “virtual” element.

The RIS 305-c may support element grouping in accordance with the RIS hardware configuration 300-c. In this example, the RIS 305-c may include or be coupled with, for example, twelve (12) elements 245 and two (2) independent control lines 310. Each grouping line 315 may be coupled with a single element 245 of the RIS 305-c, and six (6) grouping lines 315 and corresponding elements 245 may be connected to a single common control line 310. Thus, the RIS 305-c may support a capability for an element group 320-c, which may correspond to a group size of six (6) elements 245 per element group 320-c and a quantity of two (2) groups. The RIS controller 240-c may accordingly control each element group 320-c independently. As illustrated in FIG. 3, an increase in group size supported by a RIS 305 may correspond to a decrease in a quantity of control lines 310, which may decrease hardware costs associated with the RIS 305. For example, the RIS controller 240-b may apply a respective beamforming weight or RIS reflection coefficient to each element group 320-c, such that each element group 320-c may operate as a “virtual” element.

A RIS 305 may thereby be deployed with hardware components, such as control lines 310, group lines 315, elements 245, and other components, that support one or more element grouping types. Although three example RIS hardware configurations 300 are illustrated in FIG. 3, it is to be understood that a RIS 305 may be deployed with any quantity and combination of elements 245, control lines 310, and group lines 315, including the configurations illustrated in FIG. 3 and other configurations.

The element groups 320 that are supported by the RIS 305 may be based on a RIS hardware configuration 300. In some examples, the RIS 305 may share the capability for element grouping with a UE 115-a, a network entity 105-a, some other device, or any combination thereof as described with reference to FIGs. 1 and 2 to improve system performance. For example, the RIS 305 may send a capability message 225 to a network entity 105-a to indicate the grouping capability for the RIS 305. The capability message 225 may include, for example, a supported group size and a supported quantity of groups. In some examples, the network entity 105-a may select a grouping configuration based on the capability message 225 and available radio resources (time-frequency resources) , and may send a grouping message 230 to a UE 115-a to indicate the selected grouping configuration. The UE 115-a may use the selected grouping configuration for the RIS 305 to perform channel estimation (e.g., using one or more channel estimation methods) or improve channel estimation measurements.

FIG. 4 illustrates examples of RIS element grouping configurations 400. The RIS element grouping configurations 400 may implement or be implemented by aspects of the wireless communications systems 100 and 200 or the RIS hardware configurations 300, as described with reference to FIGs. 1–3. For example, FIG. 4 illustrates three example RIS element grouping configurations 400-a, 400-b, and 400-c for three RISs 405-a, 405-b, and 405-c, respectively. The RIS element grouping configurations 400 illustrate example configurations for a RIS 405 to group elements 245 into one or more element groups 410 (e.g., G1, G2, G3, etc. ) , which may represent examples of a RIS 205, elements 245, and element groups 320, as described with reference to FIGs. 1–3.

Each element group 410 in the RIS 405 may include, for example, one or more RIS elements 245 (e.g., RIS meta-elements) . In some examples, a RIS 405 may support one or more RIS element grouping configurations 400 and may share capability information with other devices to improve channel estimation methods according to aspects described herein. For example, the RIS 405 may report grouping capability information to the network entity 105-a via a capability message 225 (e.g., capability report message) , as described with reference to FIGs. 2 and 3. The capability message 225 may indicate element grouping capability information according to one or more RIS element grouping configurations 400. Although three example RIS element grouping configurations 400 are illustrated in FIG. 4, it is to be understood that a RIS 405 may support any configuration of grouping elements 245, including the configurations illustrated in FIG. 4 and other configurations.

In some examples, the RIS 405 may send the capability message 225 according to various methods (e.g., via RRC-layer signaling, or some other signaling) . For example, the RIS 405 may include a RIS controller 240, as described with reference to FIGs. 2 and 3, which may include a transmitter (e.g., transmitting antenna) to transmit the capability message 225 to the network entity 105-a. Additionally, or alternatively, the RIS 405 may receive a reference signal from the network entity 105-a and may use one or more elements 245 to alter the reference signal (e.g., change the reflection phase) when reflecting the reference signal to the network entity 105-a. For example, the capability message 225 may carry the grouping information in a phase of the reflected signal. The RIS 405 may also, for example, use similar techniques to communicate with a UE 115-a, or some other communication device.

The one or more RIS element grouping configurations 400 may be classified as an even grouping configuration, an uneven grouping configuration, or according to some other classification. The RIS 405 may include a grouping classification in the capability message 225. An even grouping configuration may indicate that a size of each element group 410 is the same for each element group 410 (e.g., all element groups G1, ..., GN are the same size) . Additionally, or alternatively, an uneven grouping configuration may indicate that at least one element group 410 may have a different element group size than one or more other element groups 410 (e.g., all element groups G1, ..., GN are not the same size) . In some examples, each element group 410 in the RIS 405 may have a different size.

If the grouping configuration 400 is classified as even, the RIS 405 may report capability information according to various techniques. In some examples, the RIS 405 may report a RIS element array size to the network entity via the capability message or a previous message. The RIS element array size, M×N, may indicate a quantity of elements 245 in each dimension of the RIS 405. In such cases, the RIS 405 may report a quantity of element groups 410 in each dimension, m×n, for the whole RIS surface (e.g., 3×3 for RIS 405-a, or 4×4 for RIS 405-b) , and the network entity 105-a may determine an element group size for each element group 410 according to Equation 13. Additionally, or alternatively, if the total element array size, M×N, is not reported to the network entity 105-a, the RIS 405 may report the quantity of element groups 410 in each dimension, m×n, and may also report the size for one element group 410, l×k (e.g., 4×4 for element group 410-a, or 3×3 for element group 410-b) .

In the example of FIG. 4, the RIS 405-a may support the RIS element grouping configuration 400-a (e.g., RIS meta-element grouping type 1) , which may be an example of an even grouping configuration. The RIS 405-a may include 144 elements 245 and a total element array size of 12×12 (e.g., 12 elements in each of two dimensions of the RIS 405-a) . The RIS 405-a may include three groups in a first dimension and three groups in a second dimension (e.g., 3×3) for a total of nine element groups G1, G2, G3, G4, G5, G6, G7, G8, and G9. Each group G1–G9 may include a same quantity of elements 245 as element group 410-a, with size 4×4 (e.g., four elements 245 in each dimension, and 16 total elements 245) . The RIS 405-a may report (e.g., via the capability message 225) the total element array size, 12×12, and the quantity of groups in each dimension, 3×3, to the network entity 105-a. Thus, the network entity 105-a may determine that the size for each element group G1–G9 is 4×4, according to Equation 13. Additionally, or alternatively, the RIS 405-a may not report the total element array size to the network entity 105-a. As such, the RIS 405-a may report the quantity of groups in each dimension, 3×3, and also report the element group size for one element group 410-a, 4×4.

Additionally, or alternatively, the RIS 405-b may support the RIS element grouping configuration 400-b (e.g., RIS meta-element grouping type 2) , which may be an example of an even grouping configuration. The RIS 405-b may include 144 elements 245 and a total element array size of 12×12. The RIS 405-b may include four groups in a first dimension and four groups in a second dimension (e.g., 4×4) for a total of 16 element groups G1, G2, G3, G4, G5, G6, G7, G8, G9, G10, G11, G12, G13, G14, G15, and G16. Each group G1–G16 may include a same quantity of elements as element group 410-b with size 3×3 (e.g., three elements 245 in each dimension, and nine total elements 245) . The RIS 405-b may report (e.g., via the capability message 225) the total element array size, 12×12, and the quantity of groups in each dimension, 4×4, to the network entity 105-a. Thus, the network entity 105-a may determine the size for each element group G1–G16, 3×3, according to Equation 13. Additionally, or alternatively, the RIS 405-b may not report the total group size, and may report the quantity of groups in each dimension, 4×4, and the element group size for one element group 410-b (e.g., 3×3) to the network entity 105-a.

In some examples, the group configuration 400 may be uneven, where each element group is not a same size. In such examples where the grouping configurations 400 are classified as uneven, the RIS 405 may report capability information for each element group (e.g., G1, G2, G3, and so on) . For example, the RIS 405 may report the total element array size, M×N, and a total quantity of element groups, G. The RIS 405 may report a ratio, α_i×β_i, for each element group, where 0<α_i<1, 0<β_i<1, and i=1～G. Thus, the element group size for an element group i (e.g., the ith group) may be determined according to Equation 14. Additionally, or alternatively, the RIS 405 may report a total quantity of element groups, G, and directly report the element group size, l_i×k_i, for each element group, i=1～G.

element group size= Mα_i×Nβ_i (14)

In the example of FIG. 4, the RIS 405-c may support the RIS element grouping configuration 400-c, which may be an example of an uneven grouping configuration 400. The RIS 405-c may include 144 elements 245 and a total element array size of 12×12. The RIS 405-c may include three groups in a first dimension and three groups in a second dimension (e.g., 3×3) for a total of nine element groups G1, G2, G3, G4, G5, G6, G7, G8, and G9. The RIS 405-c may include one or more element groups with different element group sizes. For instance, group G1 may be associated with element group 410-c and group G3 may be associated with element group 410-d. Element group 410-c may have size 3×3 and element group 410-d may have size 4×4. Thus, the RIS 405-c may report grouping information for each element group (e.g., G1, G2, G3, and so on) . In some examples, the RIS 405-c may report the total element array size, 12×12, a total quantity of nine groups, and a ratio for each group, α_i×β_i, to the network entity 105-a (e.g., via capability message 225) . For instance, the ratio for element group G1 may beand the ratio for element group G2 may be Thus, the network entity 105-a may determine that the element group 410-c size for group G1 is 3×3 and the element group 410-d size for group G3 is 4×4, according to Equation 14. Additionally, or alternatively, the RIS 405-c may report a quantity of nine groups, and directly report the element group size, l_i×k_i, for each group G1–G9 (e.g., report 3×3 for G1, report 4×4 for G3, etc. ) to the network entity 105-a.

The network entity 105-a may receive a capability message 225 (e.g., capability report) including grouping capability information for the RIS 405 and determine (e.g., select) a RIS element grouping type. The network entity 105-a may determine the RIS element grouping type and associated radio resources for performing channel estimation (e.g., RIS reflection link channel estimation) based on the capability message 225, available radio resources, or both. In some examples, the network entity 105-a may indicate a group expanding factor for adjusting a RIS element grouping type supported by the RIS 405 based on a quantity of available resources (e.g., CSI-RS resources) . The expanding factor may correspond to a factor for decreasing a quantity of element groups 410 and increasing an element group size relative to the reported element grouping capabilities of the RIS 405.

For example, the RIS 405-b and may send the capability message 225 to the network entity 105-a indicating that the RIS 405-b supports RIS element grouping configuration 400-b. If the quantity of available radio resources (e.g., resources available for CSI-RS) is relatively large (e.g., 16 resources or some other quantity of resources that is the same as or greater than a quantity of element groups 410 supported by the RIS) , the network entity 105-a may determine to use a same RIS element grouping type as reported in the capability message 225 (e.g., 16 total groups each with element group size 3×3) . Thus, the network entity 105-a may indicate a group expanding factor of one (e.g., one resource available per element group) . Additionally, or alternatively, if the quantity of available radio resources is relatively small (e.g., four resources or some other quantity of resources that is less than a quantity of element groups 410 supported by the RIS) , the network entity 105-a may determine to use a group expanding factor greater than one, which result in a RIS element grouping type with an increased group size from the group size reported in the capability message 225. For instance, if four resources are available, the network entity 105-a may use a group expanding factor of two, which indicate a RIS element grouping type with a double of the reported group size (e.g., 3×3) , resulting in group size 6×6 (e.g., six elements 245 in each dimension of each element group 410) .

As described with reference to FIG. 3, the RIS 405 may support one or more hardware configurations, and may operate each element group 410 using one or more control lines 310. In some examples, the RIS 405 may support fewer groups than indicated in the capability message 225 and may combine multiple element groups 410 together into one element group 410 based on the group expanding factor. For example, the network entity 105-a may indicate a group expanding factor of two to the RIS 405-b which supports RIS element grouping configuration 400-b. The RIS 405-b may accordingly combine groups G1, G2, G5, and G6, into a first element group, groups G3, G4, G7, and G8 into a second element group, groups G9, G10, G13, and G14 into a third element group, and groups G11, G12, G15, and G16 into a fourth element group. In some examples, a relatively small group expanding factor may be associated with a relatively larger achievable RIS reflection beamforming gain, while a relatively larger group expanding factor may be associated with a relatively smaller achievable RIS reflection beamforming gain.

FIG. 5 illustrates an example of a process flow 500 that supports element grouping for a RIS in accordance with one or more aspects of the present disclosure. The process flow 500 may implement or be implemented by aspects of the wireless communications systems 100 and 200, the RIS hardware configurations 300, or the RIS element grouping configurations 400. For example, a network entity 105-b, a RIS 205-b, and a UE 115-b may implement the process flow 500 to improve reflection link and direct link channel estimation procedures. The network entity 105-b, the RIS 205-b, and the UE 115-b may represent examples of the corresponding devices described with reference to FIGs. 1–4. For example, the RIS 205-b may include an array of multiple RIS elements, which may represent examples of the RIS elements 245 as described with reference to FIGs. 2–4. Alternative examples of the following may be implemented, where some steps are performed in a different order than described or are not performed at all. In some cases, steps may include additional features not mentioned below, or further steps may be added.

At 505, the RIS 205-b may transmit (e.g., the network entity 105-b may receive) a capability message that indicates one or more supported element grouping types that are supported by the RIS 205-b. Each of the one or more element grouping types may correspond to a respective pattern for grouping the RIS elements of the RIS 205-b (e.g., as described with reference to FIG. 4) . In some examples, the RIS 205-b may transmit, for each element grouping type of the one or more element grouping types supported by the RIS 205-b, an indication of a quantity of element groups. Additionally, or alternatively, the capability message may include information that indicates a quantity of elements included in each element group of the one or more element groups for each element grouping type supported by the RIS 205-b. In some examples, the quantity of elements included in each element group may be the same or different.

Additionally, or alternatively, the capability message may further include an indication of a total quantity of elements at the RIS 205-b, a quantity of element groups associated with the respective element grouping type, a ratio associated with each element group of the quantity of element groups, or some other capability information. In some examples, a quantity of elements included in each element group may be based on a product of a respective ratio associated with the element group and the total quantity of elements of the RIS 205-b.

The RIS 205-b may transmit the capability message using a RIS controller which may include a transmitter (e.g., transmitting antenna) . Additionally, or alternatively, the RIS 205-b may receive a reference signal from the network entity 105-b and may adjust a phase of the reference signal using one or more RIS elements. The RIS 205-b may include the information for the capability message in the phase of the reflected reference signal.

At 510, the network entity 105-b may determine an element grouping type for the RIS 205-b based on the capability message received in 505. For example, the network entity 105-b may select the element grouping type from the one or more element grouping types indicated via the capability message based on a set of resources allocated for reflection of one or more signals using the element grouping type. The network entity 105-b may further select a channel estimation type for the UE 115-b. In some examples, the channel estimation type may be selected from one of a per-element on-off channel estimation type, a LS channel estimation type, a CS channel estimation type, or some other channel estimation type.

In some examples, the capability message at 505 may indicate the total quantity of RIS elements and the quantity of element groups. The network entity 105-b may determine (e.g., according to Equation 13 as described with reference to FIG. 4) the quantity of RIS elements in each of the element groups. In such examples, the quantity of RIS elements in each element group of the quantity of element groups may be the same.

The network entity 105-b may determine to use a same or a different element grouping type than a first quantity of element groups indicated in the capability message at 505 based on a quantity of available resources (e.g., available CSI-RS resources) . For example, the network entity 105-b may determine an expanding factor associated with the first element grouping type and a second quantity of element groups for operations by the RIS may be based on a ratio of the first quantity of element groups and the expanding factor. The RIS 205-b may support a quantity of groups less than or the same as the quantity indicated by the capability message at 505 and may apply the expanding factor to increase the quantity of RIS elements in each element group (e.g., thereby decreasing the quantity of element groups) . The expanding factor may include a number greater than or equal to one.

The network entity 105-b may determine a pattern for alternating, by the RIS 205-b during the set of resources, between a quantity of element groups associated with the element grouping type and between corresponding reflection coefficients. For example, the network entity 105-b may configure a repetition or periodicity of a per-group on-off or a group-based beamforming gain pattern, or both. In some examples, the pattern may be based on a channel estimation type associated with one or more signals.

At 515, the network entity 105-b may transmit (e.g., the RIS 205-b may receive) a grouping message that indicates an element grouping type for the RIS 205-b, a quantity of element groups associated with the element grouping type, a type of channel estimation associated with the one or more signals, some other grouping information, or any combination thereof. The message may indicate a set of resources allocated for reflection of one or more signals (e.g., CSI-RSs or some other type of signals) using the element grouping type. In some examples, if per-element channel estimation is used or enabled, the network entity 105-b may configure a one element one time indicator for the per-element channel estimation type and a same quantity of time resources (e.g., CSI-RS radio resources or time occasions) as the quantity of element groups. Additionally, or alternatively, if LS or CS channel estimation is enabled, the network entity 105-b may configure an all element indictor for the LS or CS channel estimation type to include in the grouping message.

The grouping message may be transmitted via static signaling (e.g., RRC-layer signaling) , via dynamic signaling (e.g., MAC-CE or DCI) , or some other signaling. In some examples, the RIS 205-b may receive the grouping message using a RIS controller that is coupled with or included in the RIS 205-b. The network entity 105-b may select the element grouping type based on the one or more element grouping types indicated via the capability message at 505 and a set of resources allocated for reflection of one or more signals using the element grouping type.

The grouping message may include an indication of an expanding factor associated with an element grouping type indicated via the capability message from the RIS 205-b. The expanding factor may be based on the quantity of available resources. A second quantity of element groups for operations by the RIS 205-b may be based on a ratio of a first quantity of element groups (e.g., quantity of element groups reported at 505) associated with the element grouping type and the expanding factor.

The grouping message at 515 may further indicate an index of the element grouping type from among the one or more element grouping types indicated via the capability message at 505 (e.g., based on a reporting order in the capability message) . In some examples, the grouping message at 515 may indicate a pattern (e.g., determined at 510) for alternating, by the RIS 205-b, between a quantity of element groups of the plurality of RIS elements associated with the element grouping type, between corresponding reflection coefficients, or both.

At 520, the network entity 105-b may transmit a second grouping message to the UE 115-b that indicates an element grouping type for operations by the RIS 205-b during a set of resources. The element grouping type may correspond to a pattern for grouping RIS elements at the RIS 205-b into one or more element groups during the set of resources. The second grouping message may, in some examples, indicate a type of channel estimation associated with one or more signals conveyed via the set of resources, a quantity of element groups associated with the element grouping type for the RIS 205-b, some other grouping information, or any combination thereof. The type of channel estimation may include a per-element on-off channel estimation type, a LS channel estimation type, or a CS channel estimation type.

At 525, the network entity 105-b may transmit one or more signals during the set of resources. The network entity 105-b may transmit the one or more signals for reflection by the RIS 205-b and to the UE 115-b in accordance with the selected element grouping type indicated via the grouping messages. At 530, the RIS 205-b may operate, during the set of resources, in accordance with the element grouping type indicated via the grouping message. Operating in accordance with the element grouping type may include reflecting or refracting the one or more signals during the set of resources in accordance with the element grouping type. For example, a controller coupled with the RIS 205-b may configure or activate elements and corresponding control lines of the RIS 205-b to realize the selected element grouping type. Additionally, or alternatively, the RIS 205-b may operate, during the set of resources, according to the indication of the pattern for alternating received via the grouping message. The UE 115-b may receive the one or more signals during the set of resources, where the one or more signals are at least partially reflected by the RIS 205-b in accordance with the element grouping type.

In some examples, the RIS 205-b may indicate a first quantity of elements in each group and a first quantity of element groups at 505, but may operate (e.g., configure RIS element groups) using a second quantity elements in each group and a second quantity of element groups according to the group expanding factor received at 515. The RIS 205-b may multiply the first quantity of elements in each group by the group expanding factor to determine the second quantity of elements in each group. The RIS 205-b may divide the first quantity of element groups by the group expanding factor to determine the second quantity of element groups. The second quantity of element groups may be based on a ratio of the first quantity of element groups associated with the element grouping type and the expanding factor received at 515.

To operate in accordance with the element grouping type, the RIS 205-b may activate one or more element groups of the RIS 205-b and apply a respective RIS reflection coefficient to each element group during each resource of the set of resources in accordance with the pattern indicated via the grouping message. In some examples, if per-element on-off channel estimation is enabled, a quantity of resources (e.g., CSI-RS radio resources, time occasions) included in the set of resources may be the same as the quantity of element groups. Thus, the RIS 205-b may activate (e.g., switch on) each element group (e.g., each virtual meta-element) during each resource (e.g., in turn) based on the network entity 105-b indicating a per-element on-off channel estimation type (e.g., via a one element one time indicator) .

Additionally, or alternatively, if LS or CS channel estimation is enabled, the RIS 205-b may activate, during each resource of the set of resources in accordance with the pattern, each element group of the quantity of element groups of the RIS 205-b. The RIS 205-b may apply a respective reflection coefficient from among a set of candidate reflection coefficients to each element group of the quantity of element groups. For example, the reflection coefficients for each element in an element group may be the same, while the reflection coefficients between different elements groups may be the same or different. In some examples, the RIS 205-b may generate, during each resource of the set of resources, a respective group-based beamforming weight based on applying one or more respective reflection coefficients to the quantity of element groups. The RIS 205-b may adjust, during each resource of the set of resources, the group-based beamforming weight to generate different RIS reflection beams in accordance with the pattern. In some examples, the RIS 205-b may apply the respective reflection coefficients based on the network entity 105-b indicating a LS channel estimation type or a CS channel estimation type (e.g., via all elements indicator) .

At 535, the UE 115-b may measure the one or more signals received via the RIS 205-b and may estimate a channel based on the measurements of the one or more signals. The UE 115-b may estimate the channel in accordance with a channel estimation type from one of a per-element on-off channel estimation type, a LS channel estimation type, a CS channel estimation type, or some other channel estimation type. The channel estimation type may be indicated via the grouping messages or selected by the UE 115-b. The UE 115-b may determine or select a group-based beamforming weight associated with the RIS 205-b based on the estimated channel (e.g., an optimal group-based beamforming weight) . In some examples, the group-based beamforming weight may include a set of reflection coefficients.

If the network entity 105-b enables a per-element on-off channel estimation type or an LS-based channel estimation type, the network entity 105-b may also indicate a quantity of element groups of the RIS 205-b to the UE 115-b (e.g., via the second grouping message) . The UE 115-b may model received signals reflected by the RIS 205-b according to Equation 15, which may be based on Equation 3 as described with reference to FIG. 2.

In the example of Equation 15, the length ofmay be equal to the quantity of elements in one element group, the length ofmay be equal to the quantity of element groups (e.g., a quantity of virtual meta-elements, denoted as) , and the size of may beIn some examples, and a quantity of measurements, T, may be decreased, which may reduce the CSI-RS radio resource consumption.

The UE 115-b may estimateaccording to the per-element on/off method or LS-based method based on the element groups (e.g., virtual meta-elements) configured by the RIS 205-b at 520. In some examples (e.g., in LS-based channel estimation) , due to the element groupings, a set of RIS codewords may become andIn some examples, may have a lower rank than BB^H and calculation complexity may be reduced.

The UE 115-b may determine an ideal reflection coefficient, based on the estimatedIf all transmitting antennas are transmitting according to a precoding matrix, W_g, the received signal (e.g., in the RIS reflection link) may be modeled by Equation 16.

The UE 115-b may derive the ideal reflection coefficient, based on Equation 17. Accordingly, the ideal reflection coefficient, may be the major singular-vectors ofconsideringwhere In some examples, the UE 115-b may derive the ideal reflection coefficient, for both a reflection link and a direct link based on Equation 17 where Further, ifthenmay be the major singular-vector ofIn examples where subbands are used, ormay be an average value through all of the subbands.

In some other examples, if the network entity 105-b enables a CS-based channel estimation type, the network entity 105-b may also indicate RIS element grouping information (e.g., a meta-element grouping matrix G) to the UE 115-b via the second grouping message. The RIS element grouping information may include same information as in the capability message transmitted by the RIS 205-b (e.g., RIS 205-b capability report) for the used element grouping type (e.g., which may also be the same as the meta-element grouping matrix G) . In the CS-based channel estimation type, the RIS 205-b may generate multiple element group-based beamforming weight, for t=1～T, while the UE 115-b performs the channel estimation (e.g., signal reception measurement) . In some examples, the network entity 105-b may indicateto the UE 115-b, and the UE 115-b may perform the channel estimation according to Equation 18, and, in combination with other Equations as described with reference to FIG. 2, the UE 115-b may estimate A_m.

When the UE 115-b performs CS-based channel estimation, the UE 115-b may determine the idealwhich may satisfybased on the estimated A_m. If all transmitting antennas are transmitting according to a precoding matrix, W_g, the received signal (e.g., in the RIS reflection link) may be modeled by Equation 19.

The UE 115-b may derive the ideal reflection coefficient, for a reflection link based on Equation 20, or, if element grouping is applied at the RIS 205-b, w_r may be replaced withandmay be determined according to Equation 21, whereAccordingly, the ideal reflection coefficient, may be the major singular-vectors ofconsideringwhere In some examples, the UE 115-b may derive the ideal reflection coefficient, for both a reflection link and a direct link based on Equation 20 where Further, if element grouping is applied at RIS 205-b, andthenmay be the major singular-vector ofIn examples where subbands are used, ormay be an average value through all of the subbands.

The UE 115-b may thereby measure the one or more signals reflected or refracted by the RIS 205-b and perform a channel estimation based on the measurements. The UE 115-b may determine (e.g., calculate, estimate, or measure) an optimal beamforming weight (or) based on the measurements and the type of channel estimation performed by the UE 115-b, as described with reference to Equations 15–21. The beamforming weight may include a set of reflection coefficients, where each reflection coefficient of the set corresponds to (e.g., is applied to) a respective element group of the one or more element groups of the RIS 205-b.

At 540, the UE 115-b may transmit a CSI report to the network entity 105-b, to the RIS 205-b, or both that indicates the set of reflection coefficients determined by the UE 115-b (e.g., or) based on measurements of the one or more signals performed at 535. The UE 115-b may transmit the CSI report via static signaling (e.g., RRC-layer signaling) , dynamic signaling (e.g., MAC-CE or DCI) , or some other signaling. In some examples, the UE 115-b may transmit the CSI report to the network entity 105-b via an uplink communication link, and the network entity 105-b may forward the information to the RIS 205-b. Additionally, or alternatively, the UE 115-b may transmit the CSI report (e.g., or) directly to the RIS 205-b via a sidelink channel for subsequent (e.g., the following) control or data transmissions (e.g., PDCCH, PDSCH, PUCCH, PUSCH) . The group-based beamforming weight may be based on operations by the RIS 205-b during the set of resources. In some examples, the UE 115-b may transmit the CSI report based on determining the group-based beamforming weight at 535.

At 545, in some examples (e.g., if the UE 115-b transmits the CSI report to the network entity 105-b) , the network entity 105-b may transmit a third grouping message to the RIS 205-b based on the CSI report received from the UE 115-b. The third grouping message may indicate the group-based beamforming weight and a corresponding second element grouping type to be applied for subsequent operations by the RIS 205-b. The group-based beamforming weight may be based on operations by the RIS 205-b during the set of resources at 530. The group-based beamforming weight may include a plurality of reflection coefficients each associated with a respective element group of a set of one or more element groups associated with the second element grouping type. For example, if the network entity 105-b receives the CSI report from the UE 115-b, the network entity 105-b may forward (e.g., in a downlink channel) thereported at 540 to the RIS 205-b for subsequent (e.g., the following) control or data transmissions (e.g., PDCCH, PDSCH, PUCCH, PUSCH) along with the corresponding element grouping type.

In some examples, the third grouping message may include an indication (e.g., explicit indication) of an index of the second element grouping type (e.g., for control or data transmission) from among a set of indices associated with the one or more element grouping types indicated via the capability message at 505. For example, the index may be based on the order in the RIS 205-b capability message at 505. Additionally, or alternatively, the third grouping message may include an indication (e.g., implicit indication) of an identifier of a resource from among the set of resources (e.g., identifier of a previous CSI-RS resource) , where the group-based beamforming weight and the second element grouping type are based on the identified resource. For example, the RIS 205-b may use a same element grouping configuration as the configuration used in an identified previous CSI-RS resource.

At 550, the network entity 105-b may transmit, during a second set of resources indicated via the third grouping message, one or more second signals for reflection by the RIS 205-b. At 555, the RIS 205-b may operate, during the second set of resources, in accordance with the group-based beamforming weight and the corresponding second element grouping type indicated via the third grouping message. For example, the RIS 205-b may reconfigure the RIS elements to operate according to the information indicated in the third grouping message. As part of the operating, the RIS 205-b may reflect the one or more second signals to the UE 115-b. The UE 115-b may receive the one or more second signals that are at least partially reflected by the RIS 205-b in accordance with the plurality of reflection coefficients indicated via the CSI report at 540. In some examples, the second set of resources may be after the set of resources (e.g., resources used at 530) in time.

By performing channel estimation and reporting a selected set of reflection coefficients, the UE 115-b may ensure that subsequent communications received from the network entity 105-b via the RIS 205-b are reflected in accordance with an optimal beamforming weight, which may improve throughput and communication reliability.

FIG. 6 illustrates a block diagram 600 of a device 605 that supports element grouping for a RIS in accordance with one or more aspects of the present disclosure. The device 605 may be an example of aspects of a RIS as described herein. The device 605 may include a receiver 610, a transmitter 615, and a communications manager 620. The device 605 may also include a processor. Each of these components may be in communication with one another (e.g., via one or more buses) .

The receiver 610 may provide a means for receiving information such as packets, user data, control information, or any combination thereof associated with various information channels (e.g., control channels, data channels, information channels related to element grouping for a RIS) . Information may be passed on to other components of the device 605. The receiver 610 may utilize a single antenna or a set of multiple antennas.

The transmitter 615 may provide a means for transmitting signals generated by other components of the device 605. For example, the transmitter 615 may transmit information such as packets, user data, control information, or any combination thereof associated with various information channels (e.g., control channels, data channels, information channels related to element grouping for a RIS) . In some examples, the transmitter 615 may be co-located with a receiver 610 in a transceiver module. The transmitter 615 may utilize a single antenna or a set of multiple antennas.

The communications manager 620, the receiver 610, the transmitter 615, or various combinations thereof or various components thereof may be examples of means for performing various aspects of element grouping for a RIS as described herein. For example, the communications manager 620, the receiver 610, the transmitter 615, or various combinations or components thereof may support a method for performing one or more of the functions described herein.

In some examples, the communications manager 620, the receiver 610, the transmitter 615, or various combinations or components thereof may be implemented in hardware (e.g., in communications management circuitry) . The hardware may include a processor, a DSP, a CPU, an ASIC, an FPGA or other programmable logic device, a microcontroller, discrete gate or transistor logic, discrete hardware components, or any combination thereof configured as or otherwise supporting a means for performing the functions described in the present disclosure. In some examples, a processor and memory coupled with the processor may be configured to perform one or more of the functions described herein (e.g., by executing, by the processor, instructions stored in the memory) .

Additionally, or alternatively, in some examples, the communications manager 620, the receiver 610, the transmitter 615, or various combinations or components thereof may be implemented in code (e.g., as communications management software or firmware) executed by a processor. If implemented in code executed by a processor, the functions of the communications manager 620, the receiver 610, the transmitter 615, or various combinations or components thereof may be performed by a general-purpose processor, a DSP, a CPU, an ASIC, an FPGA, a microcontroller, or any combination of these or other programmable logic devices (e.g., configured as or otherwise supporting a means for performing the functions described in the present disclosure) .

In some examples, the communications manager 620 may be configured to perform various operations (e.g., receiving, obtaining, monitoring, outputting, transmitting) using or otherwise in cooperation with the receiver 610, the transmitter 615, or both. For example, the communications manager 620 may receive information from the receiver 610, send information to the transmitter 615, or be integrated in combination with the receiver 610, the transmitter 615, or both to obtain information, output information, or perform various other operations as described herein.

The communications manager 620 may support wireless communication at a RIS in accordance with examples as disclosed herein. For example, the communications manager 620 may be configured as or otherwise support a means for transmitting a capability message that indicates one or more element grouping types supported by the RIS, where each of the one or more element grouping types corresponds to a respective pattern for grouping a set of multiple elements of the RIS. The communications manager 620 may be configured as or otherwise support a means for receiving a message that indicates an element grouping type for the RIS, the element grouping type selected from the one or more element grouping types indicated via the capability message and a set of resources allocated for reflection of one or more signals using the element grouping type. The communications manager 620 may be configured as or otherwise support a means for operating, during the set of resources, in accordance with the element grouping type indicated via the message.

By including or configuring the communications manager 620 in accordance with examples as described herein, the device 605 (e.g., a processor controlling or otherwise coupled with the receiver 610, the transmitter 615, the communications manager 620, or a combination thereof) may support techniques for signaling to facilitate RIS element grouping, which may correspond to improved channel estimation measurements, reduced power consumption, more efficient utilization of communication resources, and improved communication reliability.

FIG. 7 illustrates a block diagram 700 of a device 705 that supports element grouping for a RIS in accordance with one or more aspects of the present disclosure. The device 705 may be an example of aspects of a device 605 or a RIS as described herein. The device 705 may include a receiver 710, a transmitter 715, and a communications manager 720. The device 705 may also include a processor. Each of these components may be in communication with one another (e.g., via one or more buses) .

The receiver 710 may provide a means for receiving information such as packets, user data, control information, or any combination thereof associated with various information channels (e.g., control channels, data channels, information channels related to element grouping for a RIS) . Information may be passed on to other components of the device 705. The receiver 710 may utilize a single antenna or a set of multiple antennas.

The transmitter 715 may provide a means for transmitting signals generated by other components of the device 705. For example, the transmitter 715 may transmit information such as packets, user data, control information, or any combination thereof associated with various information channels (e.g., control channels, data channels, information channels related to element grouping for a RIS) . In some examples, the transmitter 715 may be co-located with a receiver 710 in a transceiver module. The transmitter 715 may utilize a single antenna or a set of multiple antennas.

The device 705, or various components thereof, may be an example of means for performing various aspects of element grouping for a RIS as described herein. For example, the communications manager 720 may include a capability message component 725, a grouping configuration message component 730, an element grouping manager 735, or any combination thereof. The communications manager 720 may be an example of aspects of a communications manager 620 as described herein. In some examples, the communications manager 720, or various components thereof, may be configured to perform various operations (e.g., receiving, obtaining, monitoring, outputting, transmitting) using or otherwise in cooperation with the receiver 710, the transmitter 715, or both. For example, the communications manager 720 may receive information from the receiver 710, send information to the transmitter 715, or be integrated in combination with the receiver 710, the transmitter 715, or both to obtain information, output information, or perform various other operations as described herein.

The communications manager 720 may support wireless communication at a RIS in accordance with examples as disclosed herein. The capability message component 725 may be configured as or otherwise support a means for transmitting a capability message that indicates one or more element grouping types supported by the RIS, where each of the one or more element grouping types corresponds to a respective pattern for grouping a set of multiple elements of the RIS. The grouping configuration message component 730 may be configured as or otherwise support a means for receiving a message that indicates an element grouping type for the RIS, the element grouping type selected from the one or more element grouping types indicated via the capability message and a set of resources allocated for reflection of one or more signals using the element grouping type. The element grouping manager 735 may be configured as or otherwise support a means for operating, during the set of resources, in accordance with the element grouping type indicated via the message.

FIG. 8 illustrates a block diagram 800 of a communications manager 820 that supports element grouping for a RIS in accordance with one or more aspects of the present disclosure. The communications manager 820 may be an example of aspects of a communications manager 620, a communications manager 720, or both, as described herein. The communications manager 820, or various components thereof, may be an example of means for performing various aspects of element grouping for a RIS as described herein. For example, the communications manager 820 may include a capability message component 825, a grouping configuration message component 830, an element grouping manager 835, or any combination thereof. Each of these components may communicate, directly or indirectly, with one another (e.g., via one or more buses) .

The communications manager 820 may support wireless communication at a RIS in accordance with examples as disclosed herein. The capability message component 825 may be configured as or otherwise support a means for transmitting a capability message that indicates one or more element grouping types supported by the RIS, where each of the one or more element grouping types corresponds to a respective pattern for grouping a set of multiple elements of the RIS. The grouping configuration message component 830 may be configured as or otherwise support a means for receiving a message that indicates an element grouping type for the RIS, the element grouping type selected from the one or more element grouping types indicated via the capability message and a set of resources allocated for reflection of one or more signals using the element grouping type. The element grouping manager 835 may be configured as or otherwise support a means for operating, during the set of resources, in accordance with the element grouping type indicated via the message.

In some examples, the grouping configuration message component 830 may be configured as or otherwise support a means for receiving a second message that indicates a group-based beamforming weight and a corresponding second element grouping type to be applied for subsequent operations by the RIS, where the group-based beamforming weight is based on operations by the RIS during the set of resources, and where the group-based beamforming weight includes a set of multiple reflection coefficients each associated with a respective element group of a set of one or more element groups associated with the second element grouping type. In some examples, the element grouping manager 835 may be configured as or otherwise support a means for operating, during a second set of resources that is after the set of resources in time, in accordance with the group-based beamforming weight and the corresponding second element grouping type indicated via the second message.

In some examples, to support receiving the second message, the grouping configuration message component 830 may be configured as or otherwise support a means for receiving, via the second message, an indication of an index of the second element grouping type from among a set of indices associated with the one or more element grouping types indicated via the capability message.

In some examples, to support receiving the second message, the grouping configuration message component 830 may be configured as or otherwise support a means for receiving, via the second message, an indication of an identifier of a resource from among the set of resources, where the group-based beamforming weight and the second element grouping type are based on the identified resource.

In some examples, to support transmitting the capability message, the capability message component 825 may be configured as or otherwise support a means for transmitting, for each element grouping type of the one or more element grouping types supported by the RIS, an indication of a quantity of element groups associated with the respective element grouping type, where a quantity of elements included in each element group of the quantity of element groups is based on a total quantity of elements of the set of multiple elements of the RIS and the quantity of element groups, and where the quantity of elements included in each element group is the same.

In some examples, to support transmitting the capability message, the capability message component 825 may be configured as or otherwise support a means for transmitting, for each element grouping type of the one or more element grouping types supported by the RIS, an indication of a quantity of element groups associated with the respective element grouping type and a quantity of elements included in each element group of the quantity of element groups, where the quantity of elements in each element group is the same or different.

In some examples, to support transmitting the capability message, the capability message component 825 may be configured as or otherwise support a means for transmitting, for each element grouping type of the one or more element grouping types supported by the RIS, an indication of a total quantity of elements of the set of multiple elements of the RIS, a quantity of element groups associated with the respective element grouping type, and a ratio associated with each element group of the quantity of element groups, where a quantity of elements included in each element group is based on a product of a respective ratio associated with the element group and the total quantity of elements of the RIS.

In some examples, to support receiving the message, the grouping configuration message component 830 may be configured as or otherwise support a means for receiving, via the message, an index of the element grouping type from among the one or more element grouping types indicated via the capability message, where the element grouping type is selected from among the one or more element grouping types based on a quantity of resources included in the set of resources allocated for the reflection of the one or more signals, and where the element grouping type is associated with a first quantity of element groups. In some examples, to support receiving the message, the grouping configuration message component 830 may be configured as or otherwise support a means for receiving, via the message, an indication of an expanding factor associated with the element grouping type, the expanding factor including a number greater than or equal to one, where the expanding factor is based on the quantity of resources. In some examples, to support receiving the message, the element grouping manager 835 may be configured as or otherwise support a means for operating using a second quantity of element groups of the RIS in accordance with the element grouping type and the expanding factor, where the second quantity is based on a ratio of the first quantity of element groups associated with the element grouping type and the expanding factor.

In some examples, the message may indicate a pattern for alternating between a quantity of element groups associated with the element grouping type, and, to support operating in accordance with the element grouping type, the element grouping manager 835 may be configured as or otherwise support a means for activating, during each resource of the set of resources in accordance with the pattern, a respective element group of the quantity of element groups associated with the element grouping type, where a quantity of resources included in the set of resources is the same as the quantity of element groups, and where activating the respective element group of the RIS during each resource is based on the message indicating a per-element on-off channel estimation type.

In some examples, the message may indicate a pattern for alternating between a quantity of element groups associated with the element grouping type, and, to support operating in accordance with the element grouping type, the element grouping manager 835 may be configured as or otherwise support a means for activating, during each resource of the set of resources in accordance with the pattern, the quantity of element groups of the RIS. In some examples, to support operating in accordance with the element grouping type, the element grouping manager 835 may be configured as or otherwise support a means for applying, during each resource of the set of resources in accordance with the pattern, a respective reflection coefficient from among a set of candidate reflection coefficients to each element group of the quantity of element groups, where applying the respective reflection coefficients is based on the message indicating a LS channel estimation type or a CS channel estimation type.

In some examples, the element grouping manager 835 may be configured as or otherwise support a means for generating, during each resource of the set of resources, a respective group-based beamforming weight based on applying one or more respective reflection coefficients to the quantity of element groups.

In some examples, to support operating in accordance with the element grouping type, the element grouping manager 835 may be configured as or otherwise support a means for reflecting a set of one or more signals during the set of resources in accordance with the element grouping type.

In some examples, to support transmitting the capability message and receiving the message, the capability message component 825 may be configured as or otherwise support a means for transmitting, using a controller of the RIS, the capability message. In some examples, to support transmitting the capability message and receiving the message, the grouping configuration message component 830 may be configured as or otherwise support a means for receiving, using the controller of the RIS, the message.

FIG. 9 shows a diagram of a system 900 including a device 905 that supports network communications between RISs shows a diagram of a system 900 including a device 905 that supports element grouping for a RIS in accordance with aspects of the present disclosure. The device 905 may be an example of or include the components of a device 605, a device 705, or a RIS as described herein. The device 905 may communicate wirelessly with one or more network entities 105, UEs 115, or any combination thereof. The device 905 may include components for reflecting signals between devices, including components for transmitting and receiving communications, such as a communications manager 920, an RIS surface components controller 915 (e.g., a controller for tunable resistors and capacitors associated with each RIS element) , an RIS surface 925 (e.g., that includes an array of RIS elements) , a memory 930, code 935, and a processor 940. These components may be in electronic communication or otherwise coupled (e.g., operatively, communicatively, functionally, electronically, electrically) via one or more buses (e.g., a bus 950) .

In some cases, the device 905 may include one or more antennas for communicating with a base station (e.g., to provide capability information, communicate with other RISs, relay signaling via a UE 115 or a network entity 105, or the like) . The RIS surface 925 may reflect an impinging wave in a desired direction, via the one or more RIS elements, as described herein.

The memory 930 may include RAM and ROM. The memory 930 may store computer-readable, computer-executable code 935 including instructions that, when executed by the processor 940, cause the device 905 to perform various functions described herein. The code 935 may be stored in a non-transitory computer-readable medium such as system memory or another type of memory. In some cases, the code 935 may not be directly executable by the processor 940 but may cause a computer (e.g., when compiled and executed) to perform functions described herein. In some cases, the memory 930 may contain, among other things, a BIOS which may control basic hardware or software operation such as the interaction with peripheral components or devices.

The processor 940 may include an intelligent hardware device (e.g., a general-purpose processor, a DSP, a CPU, a microcontroller, an ASIC, an FPGA, a programmable logic device, a discrete gate or transistor logic component, a discrete hardware component, or any combination thereof) . In some cases, the processor 940 may be configured to operate a memory array using a memory controller. In some other cases, a memory controller may be integrated into the processor 940. The processor 940 may be configured to execute computer-readable instructions stored in a memory (e.g., the memory 930) to cause the device 905 to perform various functions (e.g., functions or tasks supporting network communications between RISs) . For example, the device 905 or a component of the device 905 may include a processor 940 and memory 930 coupled to the processor 940, the processor 940 and memory 930 configured to perform various functions described herein.

The communications manager 920 may support wireless communication at a RIS in accordance with examples as disclosed herein. For example, the communications manager 920 may be configured as or otherwise support a means for transmitting a capability message that indicates one or more element grouping types supported by the RIS, where each of the one or more element grouping types corresponds to a respective pattern for grouping a set of multiple elements of the RIS. The communications manager 920 may be configured as or otherwise support a means for receiving a message that indicates an element grouping type for the RIS, the element grouping type selected from the one or more element grouping types indicated via the capability message and a set of resources allocated for reflection of one or more signals using the element grouping type. The communications manager 920 may be configured as or otherwise support a means for operating, during the set of resources, in accordance with the element grouping type indicated via the message.

By including or configuring the communications manager 920 in accordance with examples as described herein, the device 905 may support techniques for signaling to facilitate RIS element grouping, which may correspond to improved channel estimation measurements, reduced power consumption, more efficient utilization of communication resources, and improved communication reliability.

In some examples, the communications manager 920 may be configured to perform various operations (e.g., receiving, monitoring, transmitting) using or otherwise in cooperation with a transceiver, one or more antennas, or any combination thereof. Although the communications manager 920 is illustrated as a separate component, in some examples, one or more functions described with reference to the communications manager 920 may be supported by or performed by the processor 940, the memory 930, the code 935, or any combination thereof. For example, the code 935 may include instructions executable by the processor 940 to cause the device 905 to perform various aspects of element grouping for a RIS as described herein, or the processor 940 and the memory 930 may be otherwise configured to perform or support such operations.

FIG. 10 illustrates a block diagram 1000 of a device 1005 that supports element grouping for a RIS in accordance with one or more aspects of the present disclosure. The device 1005 may be an example of aspects of a network entity 105 as described herein. The device 1005 may include a receiver 1010, a transmitter 1015, and a communications manager 1020. The device 1005 may also include a processor. Each of these components may be in communication with one another (e.g., via one or more buses) .

The receiver 1010 may provide a means for obtaining (e.g., receiving, determining, identifying) information such as user data, control information, or any combination thereof (e.g., I/Q samples, symbols, packets, protocol data units, service data units) associated with various channels (e.g., control channels, data channels, information channels, channels associated with a protocol stack) . Information may be passed on to other components of the device 1005. In some examples, the receiver 1010 may support obtaining information by receiving signals via one or more antennas. Additionally, or alternatively, the receiver 1010 may support obtaining information by receiving signals via one or more wired (e.g., electrical, fiber optic) interfaces, wireless interfaces, or any combination thereof.

The transmitter 1015 may provide a means for outputting (e.g., transmitting, providing, conveying, sending) information generated by other components of the device 1005. For example, the transmitter 1015 may output information such as user data, control information, or any combination thereof (e.g., I/Q samples, symbols, packets, protocol data units, service data units) associated with various channels (e.g., control channels, data channels, information channels, channels associated with a protocol stack) . In some examples, the transmitter 1015 may support outputting information by transmitting signals via one or more antennas. Additionally, or alternatively, the transmitter 1015 may support outputting information by transmitting signals via one or more wired (e.g., electrical, fiber optic) interfaces, wireless interfaces, or any combination thereof. In some examples, the transmitter 1015 and the receiver 1010 may be co-located in a transceiver, which may include or be coupled with a modem.

The communications manager 1020, the receiver 1010, the transmitter 1015, or various combinations thereof or various components thereof may be examples of means for performing various aspects of element grouping for a RIS as described herein. For example, the communications manager 1020, the receiver 1010, the transmitter 1015, or various combinations or components thereof may support a method for performing one or more of the functions described herein.

In some examples, the communications manager 1020, the receiver 1010, the transmitter 1015, or various combinations or components thereof may be implemented in hardware (e.g., in communications management circuitry) . The hardware may include a processor, a DSP, a CPU, an ASIC, an FPGA or other programmable logic device, a microcontroller, discrete gate or transistor logic, discrete hardware components, or any combination thereof configured as or otherwise supporting a means for performing the functions described in the present disclosure. In some examples, a processor and memory coupled with the processor may be configured to perform one or more of the functions described herein (e.g., by executing, by the processor, instructions stored in the memory) .

Additionally, or alternatively, in some examples, the communications manager 1020, the receiver 1010, the transmitter 1015, or various combinations or components thereof may be implemented in code (e.g., as communications management software or firmware) executed by a processor. If implemented in code executed by a processor, the functions of the communications manager 1020, the receiver 1010, the transmitter 1015, or various combinations or components thereof may be performed by a general-purpose processor, a DSP, a CPU, an ASIC, an FPGA, a microcontroller, or any combination of these or other programmable logic devices (e.g., configured as or otherwise supporting a means for performing the functions described in the present disclosure) .

In some examples, the communications manager 1020 may be configured to perform various operations (e.g., receiving, obtaining, monitoring, outputting, transmitting) using or otherwise in cooperation with the receiver 1010, the transmitter 1015, or both. For example, the communications manager 1020 may receive information from the receiver 1010, send information to the transmitter 1015, or be integrated in combination with the receiver 1010, the transmitter 1015, or both to obtain information, output information, or perform various other operations as described herein.

The communications manager 1020 may support wireless communication at a network entity in accordance with examples as disclosed herein. For example, the communications manager 1020 may be configured as or otherwise support a means for receiving a capability message that indicates one or more element grouping types supported by a RIS, where each of the one or more element grouping types corresponds to a respective pattern for grouping a set of multiple elements of the RIS. The communications manager 1020 may be configured as or otherwise support a means for transmitting a message that indicates an element grouping type for the RIS, the element grouping type selected from the one or more element grouping types indicated via the capability message and a set of resources allocated for reflection of one or more signals using the element grouping type. The communications manager 1020 may be configured as or otherwise support a means for transmitting the one or more signals during the set of resources.

By including or configuring the communications manager 1020 in accordance with examples as described herein, the device 1005 (e.g., a processor controlling or otherwise coupled with the receiver 1010, the transmitter 1015, the communications manager 1020, or a combination thereof) may support techniques for signaling to facilitate RIS element grouping, which may correspond to improved channel estimation measurements, reduced power consumption, more efficient utilization of communication resources, and improved communication reliability.

FIG. 11 illustrates a block diagram 1100 of a device 1105 that supports element grouping for a RIS in accordance with one or more aspects of the present disclosure. The device 1105 may be an example of aspects of a device 1005 or a network entity 105 as described herein. The device 1105 may include a receiver 1110, a transmitter 1115, and a communications manager 1120. The device 1105 may also include a processor. Each of these components may be in communication with one another (e.g., via one or more buses) .

The receiver 1110 may provide a means for obtaining (e.g., receiving, determining, identifying) information such as user data, control information, or any combination thereof (e.g., I/Q samples, symbols, packets, protocol data units, service data units) associated with various channels (e.g., control channels, data channels, information channels, channels associated with a protocol stack) . Information may be passed on to other components of the device 1105. In some examples, the receiver 1110 may support obtaining information by receiving signals via one or more antennas. Additionally, or alternatively, the receiver 1110 may support obtaining information by receiving signals via one or more wired (e.g., electrical, fiber optic) interfaces, wireless interfaces, or any combination thereof.

The transmitter 1115 may provide a means for outputting (e.g., transmitting, providing, conveying, sending) information generated by other components of the device 1105. For example, the transmitter 1115 may output information such as user data, control information, or any combination thereof (e.g., I/Q samples, symbols, packets, protocol data units, service data units) associated with various channels (e.g., control channels, data channels, information channels, channels associated with a protocol stack) . In some examples, the transmitter 1115 may support outputting information by transmitting signals via one or more antennas. Additionally, or alternatively, the transmitter 1115 may support outputting information by transmitting signals via one or more wired (e.g., electrical, fiber optic) interfaces, wireless interfaces, or any combination thereof. In some examples, the transmitter 1115 and the receiver 1110 may be co-located in a transceiver, which may include or be coupled with a modem.

The device 1105, or various components thereof, may be an example of means for performing various aspects of element grouping for a RIS as described herein. For example, the communications manager 1120 may include a capability message component 1125, a grouping configuration message component 1130, a signal transmitting component 1135, or any combination thereof. The communications manager 1120 may be an example of aspects of a communications manager 1020 as described herein. In some examples, the communications manager 1120, or various components thereof, may be configured to perform various operations (e.g., receiving, obtaining, monitoring, outputting, transmitting) using or otherwise in cooperation with the receiver 1110, the transmitter 1115, or both. For example, the communications manager 1120 may receive information from the receiver 1110, send information to the transmitter 1115, or be integrated in combination with the receiver 1110, the transmitter 1115, or both to obtain information, output information, or perform various other operations as described herein.

The communications manager 1120 may support wireless communication at a network entity in accordance with examples as disclosed herein. The capability message component 1125 may be configured as or otherwise support a means for receiving a capability message that indicates one or more element grouping types supported by a RIS, where each of the one or more element grouping types corresponds to a respective pattern for grouping a set of multiple elements of the RIS. The grouping configuration message component 1130 may be configured as or otherwise support a means for transmitting a message that indicates an element grouping type for the RIS, the element grouping type selected from the one or more element grouping types indicated via the capability message and a set of resources allocated for reflection of one or more signals using the element grouping type. The signal transmitting component 1135 may be configured as or otherwise support a means for transmitting the one or more signals during the set of resources.

FIG. 12 illustrates a block diagram 1200 of a communications manager 1220 that supports element grouping for a RIS in accordance with one or more aspects of the present disclosure. The communications manager 1220 may be an example of aspects of a communications manager 1020, a communications manager 1120, or both, as described herein. The communications manager 1220, or various components thereof, may be an example of means for performing various aspects of element grouping for a RIS as described herein. For example, the communications manager 1220 may include a capability message component 1225, a grouping configuration message component 1230, a signal transmitting component 1235, a report message component 1240, a channel estimation configuration message component 1245, or any combination thereof. Each of these components may communicate, directly or indirectly, with one another (e.g., via one or more buses) which may include communications within a protocol layer of a protocol stack, communications associated with a logical channel of a protocol stack (e.g., between protocol layers of a protocol stack, within a device, component, or virtualized component associated with a network entity 105, between devices, components, or virtualized components associated with a network entity 105) , or any combination thereof.

The communications manager 1220 may support wireless communication at a network entity in accordance with examples as disclosed herein. The capability message component 1225 may be configured as or otherwise support a means for receiving a capability message that indicates one or more element grouping types supported by a RIS, where each of the one or more element grouping types corresponds to a respective pattern for grouping a set of multiple elements of the RIS. The grouping configuration message component 1230 may be configured as or otherwise support a means for transmitting a message that indicates an element grouping type for the RIS, the element grouping type selected from the one or more element grouping types indicated via the capability message and a set of resources allocated for reflection of one or more signals using the element grouping type. The signal transmitting component 1235 may be configured as or otherwise support a means for transmitting the one or more signals during the set of resources.

In some examples, the report message component 1240 may be configured as or otherwise support a means for receiving, based on the one or more signals, a CSI report that indicates a group-based beamforming weight, where the group-based beamforming weight is based on operations by the RIS during the set of resources, and where the group-based beamforming weight includes a set of multiple reflection coefficients each associated with a respective element group of a set of one or more element groups of the RIS. In some examples, the grouping configuration message component 1230 may be configured as or otherwise support a means for transmitting, based on the CSI report, a second message that indicates the group-based beamforming weight and a corresponding second element grouping type to be applied for subsequent operations by the RIS.

In some examples, to support transmitting the second message, the grouping configuration message component 1230 may be configured as or otherwise support a means for transmitting, via the second message, an indication of an index of the second element grouping type from among a set of indices associated with the one or more element grouping types indicated via the capability message.

In some examples, to support transmitting the second message, the grouping configuration message component 1230 may be configured as or otherwise support a means for transmitting, via the second message, an indication of an identifier of a resource from among the set of resources, where the group-based beamforming weight and the second element grouping type are based on the identified resource.

In some examples, to support receiving the capability message, the capability message component 1225 may be configured as or otherwise support a means for receiving, for each element grouping type of the one or more element grouping types supported by the RIS, information that indicates a quantity of element groups associated with the respective element grouping type and a quantity of elements included in each element group of the one or more element groups.

In some examples, to support transmitting the message, the grouping configuration message component 1230 may be configured as or otherwise support a means for transmitting, via the message, an index of the element grouping type from among the one or more element grouping types indicated via the capability message, where the element grouping type is based on a quantity of resources included in the set of resources allocated for the reflection of the one or more signals, and where the element grouping type is associated with a first quantity of element groups. In some examples, to support transmitting the message, the grouping configuration message component 1230 may be configured as or otherwise support a means for transmitting, via the message, an indication of an expanding factor associated with the element grouping type, the expanding factor including a number greater than or equal to one, where the expanding factor is based on the quantity of resources, and where a second quantity of element groups for operations by the RIS is based on a ratio of the first quantity of element groups associated with the element grouping type and the expanding factor.

In some examples, to support transmitting the message, the grouping configuration message component 1230 may be configured as or otherwise support a means for transmitting, via the message, an indication of a pattern for alternating, by the RIS during the set of resources, between a quantity of element groups of the set of multiple elements of the RIS associated with the element grouping type and between corresponding reflection coefficients, where the pattern is based on a channel estimation type associated with the one or more signals.

In some examples, the channel estimation configuration message component 1245 may be configured as or otherwise support a means for transmitting a second message that indicates a type of channel estimation associated with the one or more signals and a quantity of element groups that is associated with the element grouping type for the RIS, where the type of channel estimation includes a per-element on-off channel estimation type, a LS channel estimation type, or a CS channel estimation type.

In some examples, to support transmitting the one or more signals, the signal transmitting component 1235 may be configured as or otherwise support a means for transmitting the one or more signals for reflection by the RIS to a UE in accordance with the element grouping type.

FIG. 13 illustrates a diagram of a system 1300 including a device 1305 that supports element grouping for a RIS in accordance with one or more aspects of the present disclosure. The device 1305 may be an example of or include the components of a device 1005, a device 1105, or a network entity 105 as described herein. The device 1305 may communicate with one or more network entities 105, one or more UEs 115, or any combination thereof, which may include communications over one or more wired interfaces, over one or more wireless interfaces, or any combination thereof. The device 1305 may include components that support outputting and obtaining communications, such as a communications manager 1320, a transceiver 1310, an antenna 1315, a memory 1325, code 1330, and a processor 1335. These components may be in electronic communication or otherwise coupled (e.g., operatively, communicatively, functionally, electronically, electrically) via one or more buses (e.g., a bus 1340) .

The transceiver 1310 may support bi-directional communications via wired links, wireless links, or both as described herein. In some examples, the transceiver 1310 may include a wired transceiver and may communicate bi-directionally with another wired transceiver. Additionally, or alternatively, in some examples, the transceiver 1310 may include a wireless transceiver and may communicate bi-directionally with another wireless transceiver. In some examples, the device 1305 may include one or more antennas 1315, which may be capable of transmitting or receiving wireless transmissions (e.g., concurrently) . The transceiver 1310 may also include a modem to modulate signals, to provide the modulated signals for transmission (e.g., by one or more antennas 1315, by a wired transmitter) , to receive modulated signals (e.g., from one or more antennas 1315, from a wired receiver) , and to demodulate signals. In some implementations, the transceiver 1310 may include one or more interfaces, such as one or more interfaces coupled with the one or more antennas 1315 that are configured to support various receiving or obtaining operations, or one or more interfaces coupled with the one or more antennas 1315 that are configured to support various transmitting or outputting operations, or a combination thereof. In some implementations, the transceiver 1310 may include or be configured for coupling with one or more processors or memory components that are operable to perform or support operations based on received or obtained information or signals, or to generate information or other signals for transmission or other outputting, or any combination thereof. In some implementations, the transceiver 1310, or the transceiver 1310 and the one or more antennas 1315, or the transceiver 1310 and the one or more antennas 1315 and one or more processors or memory components (for example, the processor 1335, or the memory 1325, or both) , may be included in a chip or chip assembly that is installed in the device 1305. In some examples, the transceiver may be operable to support communications via one or more communications links (e.g., a communication link 125, a backhaul communication link 120, a midhaul communication link 162, a fronthaul communication link 168) .

The memory 1325 may include RAM and ROM. The memory 1325 may store computer-readable, computer-executable code 1330 including instructions that, when executed by the processor 1335, cause the device 1305 to perform various functions described herein. The code 1330 may be stored in a non-transitory computer-readable medium such as system memory or another type of memory. In some cases, the code 1330 may not be directly executable by the processor 1335 but may cause a computer (e.g., when compiled and executed) to perform functions described herein. In some cases, the memory 1325 may contain, among other things, a BIOS which may control basic hardware or software operation such as the interaction with peripheral components or devices.

The processor 1335 may include an intelligent hardware device (e.g., a general-purpose processor, a DSP, an ASIC, a CPU, an FPGA, a microcontroller, a programmable logic device, discrete gate or transistor logic, a discrete hardware component, or any combination thereof) . In some cases, the processor 1335 may be configured to operate a memory array using a memory controller. In some other cases, a memory controller may be integrated into the processor 1335. The processor 1335 may be configured to execute computer-readable instructions stored in a memory (e.g., the memory 1325) to cause the device 1305 to perform various functions (e.g., functions or tasks supporting element grouping for a RIS) . For example, the device 1305 or a component of the device 1305 may include a processor 1335 and memory 1325 coupled with the processor 1335, the processor 1335 and memory 1325 configured to perform various functions described herein. The processor 1335 may be an example of a cloud-computing platform (e.g., one or more physical nodes and supporting software such as operating systems, virtual machines, or container instances) that may host the functions (e.g., by executing code 1330) to perform the functions of the device 1305. The processor 1335 may be any one or more suitable processors capable of executing scripts or instructions of one or more software programs stored in the device 1305 (such as within the memory 1325) . In some implementations, the processor 1335 may be a component of a processing system. A processing system may generally refer to a system or series of machines or components that receives inputs and processes the inputs to produce a set of outputs (which may be passed to other systems or components of, for example, the device 1305) . For example, a processing system of the device 1305 may refer to a system including the various other components or subcomponents of the device 1305, such as the processor 1335, or the transceiver 1310, or the communications manager 1320, or other components or combinations of components of the device 1305. The processing system of the device 1305 may interface with other components of the device 1305, and may process information received from other components (such as inputs or signals) or output information to other components. For example, a chip or modem of the device 1305 may include a processing system and one or more interfaces to output information, or to obtain information, or both. The one or more interfaces may be implemented as or otherwise include a first interface configured to output information and a second interface configured to obtain information, or a same interface configured to output information and to obtain information, among other implementations. In some implementations, the one or more interfaces may refer to an interface between the processing system of the chip or modem and a transmitter, such that the device 1305 may transmit information output from the chip or modem. Additionally, or alternatively, in some implementations, the one or more interfaces may refer to an interface between the processing system of the chip or modem and a receiver, such that the device 1305 may obtain information or signal inputs, and the information may be passed to the processing system. A person having ordinary skill in the art will readily recognize that a first interface also may obtain information or signal inputs, and a second interface also may output information or signal outputs.

In some examples, a bus 1340 may support communications of (e.g., within) a protocol layer of a protocol stack. In some examples, a bus 1340 may support communications associated with a logical channel of a protocol stack (e.g., between protocol layers of a protocol stack) , which may include communications performed within a component of the device 1305, or between different components of the device 1305 that may be co-located or located in different locations (e.g., where the device 1305 may refer to a system in which one or more of the communications manager 1320, the transceiver 1310, the memory 1325, the code 1330, and the processor 1335 may be located in one of the different components or divided between different components) .

In some examples, the communications manager 1320 may manage aspects of communications with a core network 130 (e.g., via one or more wired or wireless backhaul links) . For example, the communications manager 1320 may manage the transfer of data communications for client devices, such as one or more UEs 115. In some examples, the communications manager 1320 may manage communications with other network entities 105, and may include a controller or scheduler for controlling communications with UEs 115 in cooperation with other network entities 105. In some examples, the communications manager 1320 may support an X2 interface within an LTE/LTE-A wireless communications network technology to provide communication between network entities 105.

The communications manager 1320 may support wireless communication at a network entity in accordance with examples as disclosed herein. For example, the communications manager 1320 may be configured as or otherwise support a means for receiving a capability message that indicates one or more element grouping types supported by a RIS, where each of the one or more element grouping types corresponds to a respective pattern for grouping a set of multiple elements of the RIS. The communications manager 1320 may be configured as or otherwise support a means for transmitting a message that indicates an element grouping type for the RIS, the element grouping type selected from the one or more element grouping types indicated via the capability message and a set of resources allocated for reflection of one or more signals using the element grouping type. The communications manager 1320 may be configured as or otherwise support a means for transmitting the one or more signals during the set of resources.

By including or configuring the communications manager 1320 in accordance with examples as described herein, the device 1305 may support techniques for signaling to facilitate RIS element grouping, which may correspond to improved channel estimation measurements, reduced power consumption, more efficient utilization of communication resources, and improved communication reliability.

In some examples, the communications manager 1320 may be configured to perform various operations (e.g., receiving, obtaining, monitoring, outputting, transmitting) using or otherwise in cooperation with the transceiver 1310, the one or more antennas 1315 (e.g., where applicable) , or any combination thereof. Although the communications manager 1320 is illustrated as a separate component, in some examples, one or more functions described with reference to the communications manager 1320 may be supported by or performed by the transceiver 1310, the processor 1335, the memory 1325, the code 1330, or any combination thereof. For example, the code 1330 may include instructions executable by the processor 1335 to cause the device 1305 to perform various aspects of element grouping for a RIS as described herein, or the processor 1335 and the memory 1325 may be otherwise configured to perform or support such operations.

FIG. 14 illustrates a block diagram 1400 of a device 1405 that supports element grouping for a RIS in accordance with one or more aspects of the present disclosure. The device 1405 may be an example of aspects of a UE 115 as described herein. The device 1405 may include a receiver 1410, a transmitter 1415, and a communications manager 1420. The device 1405 may also include a processor. Each of these components may be in communication with one another (e.g., via one or more buses) .

The receiver 1410 may provide a means for receiving information such as packets, user data, control information, or any combination thereof associated with various information channels (e.g., control channels, data channels, information channels related to element grouping for a RIS) . Information may be passed on to other components of the device 1405. The receiver 1410 may utilize a single antenna or a set of multiple antennas.

The transmitter 1415 may provide a means for transmitting signals generated by other components of the device 1405. For example, the transmitter 1415 may transmit information such as packets, user data, control information, or any combination thereof associated with various information channels (e.g., control channels, data channels, information channels related to element grouping for a RIS) . In some examples, the transmitter 1415 may be co-located with a receiver 1410 in a transceiver module. The transmitter 1415 may utilize a single antenna or a set of multiple antennas.

The communications manager 1420, the receiver 1410, the transmitter 1415, or various combinations thereof or various components thereof may be examples of means for performing various aspects of element grouping for a RIS as described herein. For example, the communications manager 1420, the receiver 1410, the transmitter 1415, or various combinations or components thereof may support a method for performing one or more of the functions described herein.

In some examples, the communications manager 1420, the receiver 1410, the transmitter 1415, or various combinations or components thereof may be implemented in hardware (e.g., in communications management circuitry) . The hardware may include a processor, a digital signal processor (DSP) , a central processing unit (CPU) , an application-specific integrated circuit (ASIC) , a field-programmable gate array (FPGA) or other programmable logic device, a microcontroller, discrete gate or transistor logic, discrete hardware components, or any combination thereof configured as or otherwise supporting a means for performing the functions described in the present disclosure. In some examples, a processor and memory coupled with the processor may be configured to perform one or more of the functions described herein (e.g., by executing, by the processor, instructions stored in the memory) .

Additionally, or alternatively, in some examples, the communications manager 1420, the receiver 1410, the transmitter 1415, or various combinations or components thereof may be implemented in code (e.g., as communications management software or firmware) executed by a processor. If implemented in code executed by a processor, the functions of the communications manager 1420, the receiver 1410, the transmitter 1415, or various combinations or components thereof may be performed by a general-purpose processor, a DSP, a CPU, an ASIC, an FPGA, a microcontroller, or any combination of these or other programmable logic devices (e.g., configured as or otherwise supporting a means for performing the functions described in the present disclosure) .

In some examples, the communications manager 1420 may be configured to perform various operations (e.g., receiving, obtaining, monitoring, outputting, transmitting) using or otherwise in cooperation with the receiver 1410, the transmitter 1415, or both. For example, the communications manager 1420 may receive information from the receiver 1410, send information to the transmitter 1415, or be integrated in combination with the receiver 1410, the transmitter 1415, or both to obtain information, output information, or perform various other operations as described herein.

The communications manager 1420 may support wireless communication at a UE in accordance with examples as disclosed herein. For example, the communications manager 1420 may be configured as or otherwise support a means for receiving a message that indicates an element grouping type for operations by a RIS during a set of resources, where the RIS includes a set of multiple elements that support reflection of wireless signals, and where the element grouping type corresponds to a respective pattern for grouping the set of multiple elements of the RIS into one or more element groups. The communications manager 1420 may be configured as or otherwise support a means for receiving one or more signals during the set of resources, where the one or more signals are at least partially reflected by the RIS in accordance with the element grouping type. The communications manager 1420 may be configured as or otherwise support a means for transmitting a CSI report that indicates a set of multiple reflection coefficients based on measurements of the one or more signals, where each reflection coefficient of the set of multiple reflection coefficients corresponds to a respective group of the one or more element groups of the set of multiple elements of the RIS.

By including or configuring the communications manager 1420 in accordance with examples as described herein, the device 1405 (e.g., a processor controlling or otherwise coupled with the receiver 1410, the transmitter 1415, the communications manager 1420, or a combination thereof) may support techniques for signaling to facilitate RIS element grouping, which may correspond to improved channel estimation measurements, reduced power consumption, more efficient utilization of communication resources, and improved communication reliability.

FIG. 15 illustrates a block diagram 1500 of a device 1505 that supports element grouping for a RIS in accordance with one or more aspects of the present disclosure. The device 1505 may be an example of aspects of a device 1405 or a UE 115 as described herein. The device 1505 may include a receiver 1510, a transmitter 1515, and a communications manager 1520. The device 1505 may also include a processor. Each of these components may be in communication with one another (e.g., via one or more buses) .

The receiver 1510 may provide a means for receiving information such as packets, user data, control information, or any combination thereof associated with various information channels (e.g., control channels, data channels, information channels related to element grouping for a RIS) . Information may be passed on to other components of the device 1505. The receiver 1510 may utilize a single antenna or a set of multiple antennas.

The transmitter 1515 may provide a means for transmitting signals generated by other components of the device 1505. For example, the transmitter 1515 may transmit information such as packets, user data, control information, or any combination thereof associated with various information channels (e.g., control channels, data channels, information channels related to element grouping for a RIS) . In some examples, the transmitter 1515 may be co-located with a receiver 1510 in a transceiver module. The transmitter 1515 may utilize a single antenna or a set of multiple antennas.

The device 1505, or various components thereof, may be an example of means for performing various aspects of element grouping for a RIS as described herein. For example, the communications manager 1520 may include a grouping configuration message component 1525, a signal receiving component 1530, a report message component 1535, or any combination thereof. The communications manager 1520 may be an example of aspects of a communications manager 1420 as described herein. In some examples, the communications manager 1520, or various components thereof, may be configured to perform various operations (e.g., receiving, obtaining, monitoring, outputting, transmitting) using or otherwise in cooperation with the receiver 1510, the transmitter 1515, or both. For example, the communications manager 1520 may receive information from the receiver 1510, send information to the transmitter 1515, or be integrated in combination with the receiver 1510, the transmitter 1515, or both to obtain information, output information, or perform various other operations as described herein.

The communications manager 1520 may support wireless communication at a UE in accordance with examples as disclosed herein. The grouping configuration message component 1525 may be configured as or otherwise support a means for receiving a message that indicates an element grouping type for operations by a RIS during a set of resources, where the RIS includes a set of multiple elements that support reflection of wireless signals, and where the element grouping type corresponds to a respective pattern for grouping the set of multiple elements of the RIS into one or more element groups. The signal receiving component 1530 may be configured as or otherwise support a means for receiving one or more signals during the set of resources, where the one or more signals are at least partially reflected by the RIS in accordance with the element grouping type. The report message component 1535 may be configured as or otherwise support a means for transmitting a CSI report that indicates a set of multiple reflection coefficients based on measurements of the one or more signals, where each reflection coefficient of the set of multiple reflection coefficients corresponds to a respective group of the one or more element groups of the set of multiple elements of the RIS.

FIG. 16 illustrates a block diagram 1600 of a communications manager 1620 that supports element grouping for a RIS in accordance with one or more aspects of the present disclosure. The communications manager 1620 may be an example of aspects of a communications manager 1420, a communications manager 1520, or both, as described herein. The communications manager 1620, or various components thereof, may be an example of means for performing various aspects of element grouping for a RIS as described herein. For example, the communications manager 1620 may include a grouping configuration message component 1625, a signal receiving component 1630, a report message component 1635, a channel estimation component 1640, or any combination thereof. Each of these components may communicate, directly or indirectly, with one another (e.g., via one or more buses) .

The communications manager 1620 may support wireless communication at a UE in accordance with examples as disclosed herein. The grouping configuration message component 1625 may be configured as or otherwise support a means for receiving a message that indicates an element grouping type for operations by a RIS during a set of resources, where the RIS includes a set of multiple elements that support reflection of wireless signals, and where the element grouping type corresponds to a respective pattern for grouping the set of multiple elements of the RIS into one or more element groups. The signal receiving component 1630 may be configured as or otherwise support a means for receiving one or more signals during the set of resources, where the one or more signals are at least partially reflected by the RIS in accordance with the element grouping type. The report message component 1635 may be configured as or otherwise support a means for transmitting a CSI report that indicates a set of multiple reflection coefficients based on measurements of the one or more signals, where each reflection coefficient of the set of multiple reflection coefficients corresponds to a respective group of the one or more element groups of the set of multiple elements of the RIS.

In some examples, to support receiving the message, the grouping configuration message component 1625 may be configured as or otherwise support a means for receiving, via the message, an indication of a quantity of element groups included in the one or more element groups of the RIS, a quantity of elements included in each group of the one or more element groups, or both.

In some examples, the channel estimation component 1640 may be configured as or otherwise support a means for estimating a channel based on the measurements of the one or more signals. In some examples, the channel estimation component 1640 may be configured as or otherwise support a means for determining a group-based beamforming weight associated with the RIS based on the estimated channel, where the group-based beamforming weight includes the set of multiple reflection coefficients, and where transmitting the CSI report is based on determining the group-based beamforming weight.

In some examples, to support estimating the channel, the channel estimation component 1640 may be configured as or otherwise support a means for estimating the channel in accordance with a channel estimation type selected from one of a per-element on-off channel estimation type, a LS channel estimation type, or a CS channel estimation type.

In some examples, the signal receiving component 1630 may be configured as or otherwise support a means for receiving, during a second set of resources that is after the set of resources in time, one or more second signals that are at least partially reflected by the RIS in accordance with the set of multiple reflection coefficients indicated via the CSI report.

FIG. 17 illustrates a diagram of a system 1700 including a device 1705 that supports element grouping for a RIS in accordance with one or more aspects of the present disclosure. The device 1705 may be an example of or include the components of a device 1405, a device 1505, or a UE 115 as described herein. The device 1705 may communicate (e.g., wirelessly) with one or more network entities 105, one or more UEs 115, or any combination thereof. The device 1705 may include components for bi-directional voice and data communications including components for transmitting and receiving communications, such as a communications manager 1720, an input/output (I/O) controller 1710, a transceiver 1715, an antenna 1725, a memory 1730, code 1735, and a processor 1740. These components may be in electronic communication or otherwise coupled (e.g., operatively, communicatively, functionally, electronically, electrically) via one or more buses (e.g., a bus 1745) .

The I/O controller 1710 may manage input and output signals for the device 1705. The I/O controller 1710 may also manage peripherals not integrated into the device 1705. In some cases, the I/O controller 1710 may represent a physical connection or port to an external peripheral. In some cases, the I/O controller 1710 may utilize an operating system such as or another known operating system. Additionally, or alternatively, the I/O controller 1710 may represent or interact with a modem, a keyboard, a mouse, a touchscreen, or a similar device. In some cases, the I/O controller 1710 may be implemented as part of a processor, such as the processor 1740. In some cases, a user may interact with the device 1705 via the I/O controller 1710 or via hardware components controlled by the I/O controller 1710.

In some cases, the device 1705 may include a single antenna 1725. However, in some other cases, the device 1705 may have more than one antenna 1725, which may be capable of concurrently transmitting or receiving multiple wireless transmissions. The transceiver 1715 may communicate bi-directionally, via the one or more antennas 1725, wired, or wireless links as described herein. For example, the transceiver 1715 may represent a wireless transceiver and may communicate bi-directionally with another wireless transceiver. The transceiver 1715 may also include a modem to modulate the packets, to provide the modulated packets to one or more antennas 1725 for transmission, and to demodulate packets received from the one or more antennas 1725. The transceiver 1715, or the transceiver 1715 and one or more antennas 1725, may be an example of a transmitter 1415, a transmitter 1515, a receiver 1410, a receiver 1510, or any combination thereof or component thereof, as described herein.

The memory 1730 may include random access memory (RAM) and read-only memory (ROM) . The memory 1730 may store computer-readable, computer-executable code 1735 including instructions that, when executed by the processor 1740, cause the device 1705 to perform various functions described herein. The code 1735 may be stored in a non-transitory computer-readable medium such as system memory or another type of memory. In some cases, the code 1735 may not be directly executable by the processor 1740 but may cause a computer (e.g., when compiled and executed) to perform functions described herein. In some cases, the memory 1730 may contain, among other things, a basic I/O system (BIOS) which may control basic hardware or software operation such as the interaction with peripheral components or devices.

The processor 1740 may include an intelligent hardware device (e.g., a general-purpose processor, a DSP, a CPU, a microcontroller, an ASIC, an FPGA, a programmable logic device, a discrete gate or transistor logic component, a discrete hardware component, or any combination thereof) . In some cases, the processor 1740 may be configured to operate a memory array using a memory controller. In some other cases, a memory controller may be integrated into the processor 1740. The processor 1740 may be configured to execute computer-readable instructions stored in a memory (e.g., the memory 1730) to cause the device 1705 to perform various functions (e.g., functions or tasks supporting element grouping for a RIS) . For example, the device 1705 or a component of the device 1705 may include a processor 1740 and memory 1730 coupled with or to the processor 1740, the processor 1740 and memory 1730 configured to perform various functions described herein.

The communications manager 1720 may support wireless communication at a UE in accordance with examples as disclosed herein. For example, the communications manager 1720 may be configured as or otherwise support a means for receiving a message that indicates an element grouping type for operations by a RIS during a set of resources, where the RIS includes a set of multiple elements that support reflection of wireless signals, and where the element grouping type corresponds to a respective pattern for grouping the set of multiple elements of the RIS into one or more element groups. The communications manager 1720 may be configured as or otherwise support a means for receiving one or more signals during the set of resources, where the one or more signals are at least partially reflected by the RIS in accordance with the element grouping type. The communications manager 1720 may be configured as or otherwise support a means for transmitting a CSI report that indicates a set of multiple reflection coefficients based on measurements of the one or more signals, where each reflection coefficient of the set of multiple reflection coefficients corresponds to a respective group of the one or more element groups of the set of multiple elements of the RIS.

By including or configuring the communications manager 1720 in accordance with examples as described herein, the device 1705 may support techniques for signaling to facilitate RIS element grouping, which may correspond to improved channel estimation measurements, reduced power consumption, more efficient utilization of communication resources, and improved communication reliability.

In some examples, the communications manager 1720 may be configured to perform various operations (e.g., receiving, monitoring, transmitting) using or otherwise in cooperation with the transceiver 1715, the one or more antennas 1725, or any combination thereof. Although the communications manager 1720 is illustrated as a separate component, in some examples, one or more functions described with reference to the communications manager 1720 may be supported by or performed by the processor 1740, the memory 1730, the code 1735, or any combination thereof. For example, the code 1735 may include instructions executable by the processor 1740 to cause the device 1705 to perform various aspects of element grouping for a RIS as described herein, or the processor 1740 and the memory 1730 may be otherwise configured to perform or support such operations.

FIG. 18 illustrates a flowchart showing a method 1800 that supports element grouping for a RIS in accordance with one or more aspects of the present disclosure. The operations of the method 1800 may be implemented by a RIS or its components as described herein. For example, the operations of the method 1800 may be performed by a RIS as described with reference to FIGs. 1 through 9. In some examples, a RIS may execute a set of instructions to control the functional elements of the RIS to perform the described functions. Additionally, or alternatively, the RIS may perform aspects of the described functions using special-purpose hardware.

At 1805, the method may include transmitting a capability message that indicates one or more element grouping types supported by the RIS, where each of the one or more element grouping types corresponds to a respective pattern for grouping a set of multiple elements of the RIS. The operations of 1805 may be performed in accordance with examples as disclosed herein. In some examples, aspects of the operations of 1805 may be performed by a capability message component 825 as described with reference to FIG. 8.

At 1810, the method may include receiving a message that indicates an element grouping type for the RIS, the element grouping type selected from the one or more element grouping types indicated via the capability message and a set of resources allocated for reflection of one or more signals using the element grouping type. The operations of 1810 may be performed in accordance with examples as disclosed herein. In some examples, aspects of the operations of 1810 may be performed by a grouping configuration message component 830 as described with reference to FIG. 8.

At 1815, the method may include operating, during the set of resources, in accordance with the element grouping type indicated via the message. The operations of 1815 may be performed in accordance with examples as disclosed herein. In some examples, aspects of the operations of 1815 may be performed by an element grouping manager 835 as described with reference to FIG. 8.

FIG. 19 illustrates a flowchart showing a method 1900 that supports element grouping for a RIS in accordance with one or more aspects of the present disclosure. The operations of the method 1900 may be implemented by a network entity or its components as described herein. For example, the operations of the method 1900 may be performed by a network entity as described with reference to FIGs. 1 through 5 and 10 through 13. In some examples, a network entity may execute a set of instructions to control the functional elements of the network entity to perform the described functions. Additionally, or alternatively, the network entity may perform aspects of the described functions using special-purpose hardware.

At 1905, the method may include receiving a capability message that indicates one or more element grouping types supported by a RIS, where each of the one or more element grouping types corresponds to a respective pattern for grouping a set of multiple elements of the RIS. The operations of 1905 may be performed in accordance with examples as disclosed herein. In some examples, aspects of the operations of 1905 may be performed by a capability message component 1225 as described with reference to FIG. 12.

At 1910, the method may include transmitting a message that indicates an element grouping type for the RIS, the element grouping type selected from the one or more element grouping types indicated via the capability message and a set of resources allocated for reflection of one or more signals using the element grouping type. The operations of 1910 may be performed in accordance with examples as disclosed herein. In some examples, aspects of the operations of 1910 may be performed by a grouping configuration message component 1230 as described with reference to FIG. 12.

At 1915, the method may include transmitting the one or more signals during the set of resources. The operations of 1915 may be performed in accordance with examples as disclosed herein. In some examples, aspects of the operations of 1915 may be performed by a signal transmitting component 1235 as described with reference to FIG. 12.

FIG. 20 illustrates a flowchart showing a method 2000 that supports element grouping for a RIS in accordance with one or more aspects of the present disclosure. The operations of the method 2000 may be implemented by a UE or its components as described herein. For example, the operations of the method 2000 may be performed by a UE 115 as described with reference to FIGs. 1 through 5 and 14 through 17. In some examples, a UE may execute a set of instructions to control the functional elements of the UE to perform the described functions. Additionally, or alternatively, the UE may perform aspects of the described functions using special-purpose hardware.

At 2005, the method may include receiving a message that indicates an element grouping type for operations by a RIS during a set of resources, where the RIS includes a set of multiple elements that support reflection of wireless signals, and where the element grouping type corresponds to a respective pattern for grouping the set of multiple elements of the RIS into one or more element groups. The operations of 2005 may be performed in accordance with examples as disclosed herein. In some examples, aspects of the operations of 2005 may be performed by a grouping configuration message component 1625 as described with reference to FIG. 16.

At 2010, the method may include receiving one or more signals during the set of resources, where the one or more signals are at least partially reflected by the RIS in accordance with the element grouping type. The operations of 2010 may be performed in accordance with examples as disclosed herein. In some examples, aspects of the operations of 2010 may be performed by a signal receiving component 1630 as described with reference to FIG. 16.

At 2015, the method may include transmitting a CSI report that indicates a set of multiple reflection coefficients based on measurements of the one or more signals, where each reflection coefficient of the set of multiple reflection coefficients corresponds to a respective group of the one or more element groups of the set of multiple elements of the RIS. The operations of 2015 may be performed in accordance with examples as disclosed herein. In some examples, aspects of the operations of 2015 may be performed by a report message component 1635 as described with reference to FIG. 16.

The following provides an overview of aspects of the present disclosure:

Aspect 1: A method for wireless communication at a RIS, comprising: transmitting a capability message that indicates one or more element grouping types supported by the RIS, wherein each of the one or more element grouping types corresponds to a respective pattern for grouping a plurality of elements of the RIS; receiving a message that indicates an element grouping type for the RIS, the element grouping type selected from the one or more element grouping types indicated via the capability message and a set of resources allocated for reflection of one or more signals using the element grouping type; and operating, during the set of resources, in accordance with the element grouping type indicated via the message.

Aspect 2: The method of aspect 1, further comprising: receiving a second message that indicates a group-based beamforming weight and a corresponding second element grouping type to be applied for subsequent operations by the RIS, wherein the group-based beamforming weight is based at least in part on operations by the RIS during the set of resources, and wherein the group-based beamforming weight comprises a plurality of reflection coefficients each associated with a respective element group of a set of one or more element groups associated with the second element grouping type; and operating, during a second set of resources that is after the set of resources in time, in accordance with the group-based beamforming weight and the corresponding second element grouping type indicated via the second message.

Aspect 3: The method of aspect 2, wherein receiving the second message comprises: receiving, via the second message, an indication of an index of the second element grouping type from among a set of indices associated with the one or more element grouping types indicated via the capability message.

Aspect 4: The method of aspect 2, wherein receiving the second message comprises: receiving, via the second message, an indication of an identifier of a resource from among the set of resources, wherein the group-based beamforming weight and the second element grouping type are based at least in part on the identified resource.

Aspect 5: The method of any of aspects 1 through 4, wherein transmitting the capability message comprises: transmitting, for each element grouping type of the one or more element grouping types supported by the RIS, an indication of a quantity of element groups associated with the respective element grouping type, wherein a quantity of elements included in each element group of the quantity of element groups is based at least in part on a total quantity of elements of the plurality of elements of the RIS and the quantity of element groups, and wherein the quantity of elements included in each element group is the same.

Aspect 6: The method of any of aspects 1 through 4, wherein transmitting the capability message comprises: transmitting, for each element grouping type of the one or more element grouping types supported by the RIS, an indication of a quantity of element groups associated with the respective element grouping type and a quantity of elements included in each element group of the quantity of element groups, wherein the quantity of elements in each element group is the same or different.

Aspect 7: The method of any of aspects 1 through 4, wherein transmitting the capability message comprises: transmitting, for each element grouping type of the one or more element grouping types supported by the RIS, an indication of a total quantity of elements of the plurality of elements of the RIS, a quantity of element groups associated with the respective element grouping type, and a ratio associated with each element group of the quantity of element groups, wherein a quantity of elements included in each element group is based at least in part on a product of a respective ratio associated with the element group and the total quantity of elements of the RIS.

Aspect 8: The method of any of aspects 1 through 7, wherein receiving the message comprises: receiving, via the message, an index of the element grouping type from among the one or more element grouping types indicated via the capability message, wherein the element grouping type is selected from among the one or more element grouping types based at least in part on a quantity of resources included in the set of resources allocated for the reflection of the one or more signals, and wherein the element grouping type is associated with a first quantity of element groups; receiving, via the message, an indication of an expanding factor associated with the element grouping type, the expanding factor comprising a number greater than or equal to one, wherein the expanding factor is based at least in part on the quantity of resources; and operating using a second quantity of element groups of the RIS in accordance with the element grouping type and the expanding factor, wherein the second quantity is based at least in part on a ratio of the first quantity of element groups associated with the element grouping type and the expanding factor.

Aspect 9: The method of any of aspects 1 through 8, wherein the message indicates a pattern for alternating between a quantity of element groups associated with the element grouping type, and wherein operating in accordance with the element grouping type comprises: activating, during each resource of the set of resources in accordance with the pattern, a respective element group of the quantity of element groups associated with the element grouping type, wherein a quantity of resources included in the set of resources is the same as the quantity of element groups, and wherein activating the respective element group of the RIS during each resource is based at least in part on the message indicating a per-element on-off channel estimation type.

Aspect 10: The method of any of aspects 1 through 8, wherein the message indicates a pattern for alternating between a quantity of element groups associated with the element grouping type, and wherein operating in accordance with the element grouping type comprises: activating, during each resource of the set of resources in accordance with the pattern, the quantity of element groups of the RIS; and applying, during each resource of the set of resources in accordance with the pattern, a respective reflection coefficient from among a set of candidate reflection coefficients to each element group of the quantity of element groups, wherein applying the respective reflection coefficients is based at least in part on the message indicating a LS channel estimation type or a CS channel estimation type.

Aspect 11: The method of aspect 10, further comprising: generating, during each resource of the set of resources, a respective group-based beamforming weight based at least in part on applying one or more respective reflection coefficients to the quantity of element groups.

Aspect 12: The method of any of aspects 1 through 11, wherein operating in accordance with the element grouping type comprises: reflecting a set of one or more signals during the set of resources in accordance with the element grouping type.

Aspect 13: The method of any of aspects 1 through 12, wherein transmitting the capability message and receiving the message comprises: transmitting, using a controller of the RIS, the capability message; and receiving, using the controller of the RIS, the message.

Aspect 14: A method for wireless communication at a network entity, comprising: receiving a capability message that indicates one or more element grouping types supported by a RIS, wherein each of the one or more element grouping types corresponds to a respective pattern for grouping a plurality of elements of the RIS; transmitting a message that indicates an element grouping type for the RIS, the element grouping type selected from the one or more element grouping types indicated via the capability message and a set of resources allocated for reflection of one or more signals using the element grouping type; and transmitting the one or more signals during the set of resources.

Aspect 15: The method of aspect 14, further comprising: receiving, based at least in part on the one or more signals, a CSI report that indicates a group-based beamforming weight, wherein the group-based beamforming weight is based at least in part on operations by the RIS during the set of resources, and wherein the group-based beamforming weight comprises a plurality of reflection coefficients each associated with a respective element group of a set of one or more element groups of the RIS; and transmitting, based at least in part on the CSI report, a second message that indicates the group-based beamforming weight and a corresponding second element grouping type to be applied for subsequent operations by the RIS.

Aspect 16: The method of aspect 15, wherein transmitting the second message comprises: transmitting, via the second message, an indication of an index of the second element grouping type from among a set of indices associated with the one or more element grouping types indicated via the capability message.

Aspect 17: The method of aspect 15, wherein transmitting the second message comprises: transmitting, via the second message, an indication of an identifier of a resource from among the set of resources, wherein the group-based beamforming weight and the second element grouping type are based at least in part on the identified resource.

Aspect 18: The method of any of aspects 14 through 17, wherein receiving the capability message comprises: receiving, for each element grouping type of the one or more element grouping types supported by the RIS, information that indicates a quantity of element groups associated with the respective element grouping type and a quantity of elements included in each element group of the one or more element groups.

Aspect 19: The method of any of aspects 14 through 18, wherein transmitting the message comprises: transmitting, via the message, an index of the element grouping type from among the one or more element grouping types indicated via the capability message, wherein the element grouping type is based at least in part on a quantity of resources included in the set of resources allocated for the reflection of the one or more signals, and wherein the element grouping type is associated with a first quantity of element groups; and transmitting, via the message, an indication of an expanding factor associated with the element grouping type, the expanding factor comprising a number greater than or equal to one, wherein the expanding factor is based at least in part on the quantity of resources, and wherein a second quantity of element groups for operations by the RIS is based at least in part on a ratio of the first quantity of element groups associated with the element grouping type and the expanding factor.

Aspect 20: The method of any of aspects 14 through 19, wherein transmitting the message comprises: transmitting, via the message, an indication of a pattern for alternating, by the RIS during the set of resources, between a quantity of element groups of the plurality of elements of the RIS associated with the element grouping type and between corresponding reflection coefficients, wherein the pattern is based at least in part on a channel estimation type associated with the one or more signals.

Aspect 21: The method of any of aspects 14 through 20, further comprising: transmitting a second message that indicates a type of channel estimation associated with the one or more signals and a quantity of element groups that is associated with the element grouping type for the RIS, wherein the type of channel estimation comprises a per-element on-off channel estimation type, a LS channel estimation type, or a CS channel estimation type.

Aspect 22: The method of any of aspects 14 through 21, wherein transmitting the one or more signals comprises: transmitting the one or more signals for reflection by the RIS to a UE in accordance with the element grouping type.

Aspect 23: A method for wireless communication at a UE, comprising: receiving a message that indicates an element grouping type for operations by a RIS during a set of resources, wherein the RIS comprises a plurality of elements that support reflection of wireless signals, and wherein the element grouping type corresponds to a respective pattern for grouping the plurality of elements of the RIS into one or more element groups; receiving one or more signals during the set of resources, wherein the one or more signals are at least partially reflected by the RIS in accordance with the element grouping type; and transmitting a CSI report that indicates a plurality of reflection coefficients based at least in part on measurements of the one or more signals, wherein each reflection coefficient of the plurality of reflection coefficients corresponds to a respective group of the one or more element groups of the plurality of elements of the RIS.

Aspect 24: The method of aspect 23, wherein receiving the message comprises: receiving, via the message, an indication of a quantity of element groups included in the one or more element groups of the RIS, a quantity of elements included in each group of the one or more element groups, or both.

Aspect 25: The method of any of aspects 23 through 24, further comprising: estimating a channel based at least in part on the measurements of the one or more signals; and determining a group-based beamforming weight associated with the RIS based at least in part on the estimated channel, wherein the group-based beamforming weight comprises the plurality of reflection coefficients, and wherein transmitting the CSI report is based at least in part on determining the group-based beamforming weight.

Aspect 26: The method of aspect 25, wherein estimating the channel comprises: estimating the channel in accordance with a channel estimation type selected from one of a per-element on-off channel estimation type, a LS channel estimation type, or a CS channel estimation type.

Aspect 27: The method of any of aspects 23 through 26, further comprising: receiving, during a second set of resources that is after the set of resources in time, one or more second signals that are at least partially reflected by the RIS in accordance with the plurality of reflection coefficients indicated via the CSI report.

Aspect 28: An apparatus for wireless communication at a RIS, comprising a processor; memory coupled with the processor; and instructions stored in the memory and executable by the processor to cause the apparatus to perform a method of any of aspects 1 through 13.

Aspect 29: An apparatus for wireless communication at a RIS, comprising at least one means for performing a method of any of aspects 1 through 13.

Aspect 30: A non-transitory computer-readable medium storing code for wireless communication at a RIS, the code comprising instructions executable by a processor to perform a method of any of aspects 1 through 13.

Aspect 31: An apparatus for wireless communication at a network entity, comprising a processor; memory coupled with the processor; and instructions stored in the memory and executable by the processor to cause the apparatus to perform a method of any of aspects 14 through 22.

Aspect 32: An apparatus for wireless communication at a network entity, comprising at least one means for performing a method of any of aspects 14 through 22.

Aspect 33: A non-transitory computer-readable medium storing code for wireless communication at a network entity, the code comprising instructions executable by a processor to perform a method of any of aspects 14 through 22.

Aspect 34: An apparatus for wireless communication at a UE, comprising a processor; memory coupled with the processor; and instructions stored in the memory and executable by the processor to cause the apparatus to perform a method of any of aspects 23 through 27.

Aspect 35: An apparatus for wireless communication at a UE, comprising at least one means for performing a method of any of aspects 23 through 27.

Aspect 36: A non-transitory computer-readable medium storing code for wireless communication at a UE, the code comprising instructions executable by a processor to perform a method of any of aspects 23 through 27.

It should be noted that the methods described herein describe possible implementations, and that the operations and the steps may be rearranged or otherwise modified and that other implementations are possible. Further, aspects from two or more of the methods may be combined.

Although aspects of an LTE, LTE-A, LTE-A Pro, or NR system may be described for purposes of example, and LTE, LTE-A, LTE-A Pro, or NR terminology may be used in much of the description, the techniques described herein are applicable beyond LTE, LTE-A, LTE-A Pro, or NR networks. For example, the described techniques may be applicable to various other wireless communications systems such as Ultra Mobile Broadband (UMB) , Institute of Electrical and Electronics Engineers (IEEE) 802.11 (Wi-Fi) , IEEE 802.16 (WiMAX) , IEEE 802.20, Flash-OFDM, as well as other systems and radio technologies not explicitly mentioned herein.

Information and signals described herein may be represented using any of a variety of different technologies and techniques. For example, data, instructions, commands, information, signals, bits, symbols, and chips that may be referenced throughout the description may be represented by voltages, currents, electromagnetic waves, magnetic fields or particles, optical fields or particles, or any combination thereof.

The various illustrative blocks and components described in connection with the disclosure herein may be implemented or performed using a general-purpose processor, a DSP, an ASIC, a CPU, an FPGA or other programmable logic device, discrete gate or transistor logic, discrete hardware components, or any combination thereof designed to perform the functions described herein. A general-purpose processor may be a microprocessor but, in the alternative, the processor may be any processor, controller, microcontroller, or state machine. A processor may also be implemented as a combination of computing devices (e.g., a combination of a DSP and a microprocessor, multiple microprocessors, one or more microprocessors in conjunction with a DSP core, or any other such configuration) .

The functions described herein may be implemented using hardware, software executed by a processor, firmware, or any combination thereof. If implemented using software executed by a processor, the functions may be stored as or transmitted using one or more instructions or code of a computer-readable medium. Other examples and implementations are within the scope of the disclosure and appended claims. For example, due to the nature of software, functions described herein may be implemented using software executed by a processor, hardware, firmware, hardwiring, or combinations of any of these. Features implementing functions may also be physically located at various positions, including being distributed such that portions of functions are implemented at different physical locations.

Computer-readable media includes both non-transitory computer storage media and communication media including any medium that facilitates transfer of a computer program from one location to another. A non-transitory storage medium may be any available medium that may be accessed by a general-purpose or special-purpose computer. By way of example, and not limitation, non-transitory computer-readable media may include RAM, ROM, electrically erasable programmable ROM (EEPROM) , flash memory, compact disk (CD) ROM or other optical disk storage, magnetic disk storage or other magnetic storage devices, or any other non-transitory medium that may be used to carry or store desired program code means in the form of instructions or data structures and that may be accessed by a general-purpose or special-purpose computer, or a general-purpose or special-purpose processor. Also, any connection is properly termed a computer-readable medium. For example, if the software is transmitted from a website, server, or other remote source using a coaxial cable, fiber optic cable, twisted pair, digital subscriber line (DSL) , or wireless technologies such as infrared, radio, and microwave, then the coaxial cable, fiber optic cable, twisted pair, DSL, or wireless technologies such as infrared, radio, and microwave are included in the definition of computer-readable medium. Disk and disc, as used herein, include CD, laser disc, optical disc, digital versatile disc (DVD) , floppy disk and Blu-ray disc. Disks may reproduce data magnetically, and discs may reproduce data optically using lasers. Combinations of the above are also included within the scope of computer-readable media.

As used herein, including in the claims, “or” as used in a list of items (e.g., a list of items prefaced by a phrase such as “at least one of” or “one or more of” ) indicates an inclusive list such that, for example, a list of at least one of A, B, or C means A or B or C or AB or AC or BC or ABC (i.e., A and B and C) . Also, as used herein, the phrase “based on” shall not be construed as a reference to a closed set of conditions. For example, an example step that is described as “based on condition A” may be based on both a condition A and a condition B without departing from the scope of the present disclosure. In other words, as used herein, the phrase “based on” shall be construed in the same manner as the phrase “based at least in part on. ”

The term “determine” or “determining” encompasses a variety of actions and, therefore, “determining” can include calculating, computing, processing, deriving, investigating, looking up (such as via looking up in a table, a database or another data structure) , ascertaining and the like. Also, “determining” can include receiving (e.g., receiving information) , accessing (e.g., accessing data stored in memory) and the like. Also, “determining” can include resolving, obtaining, selecting, choosing, establishing, and other such similar actions.

In the appended figures, similar components or features may have the same reference label. Further, various components of the same type may be distinguished by following the reference label by a dash and a second label that distinguishes among the similar components. If just the first reference label is used in the specification, the description is applicable to any one of the similar components having the same first reference label irrespective of the second reference label, or other subsequent reference label.

The description set forth herein, in connection with the appended drawings, describes example configurations and does not represent all the examples that may be implemented or that are within the scope of the claims. The term “example” used herein means “serving as an example, instance, or illustration, ” and not “preferred” or “advantageous over other examples. ” The detailed description includes specific details for the purpose of providing an understanding of the described techniques. These techniques, however, may be practiced without these specific details. In some instances, known structures and devices are shown in block diagram form in order to avoid obscuring the concepts of the described examples.

The description herein is provided to enable a person having ordinary skill in the art to make or use the disclosure. Various modifications to the disclosure will be apparent to a person having ordinary skill in the art, and the generic principles defined herein may be applied to other variations without departing from the scope of the disclosure. Thus, the disclosure is not limited to the examples and designs described herein but is to be accorded the broadest scope consistent with the principles and novel features disclosed herein.

Claims

An apparatus for wireless communication at a reconfigurable intelligent surface, comprising:

a processor;

memory coupled with the processor; and

instructions stored in the memory and executable by the processor to cause the apparatus to:

transmit a capability message that indicates one or more element grouping types supported by the reconfigurable intelligent surface, wherein each of the one or more element grouping types corresponds to a respective pattern for grouping a plurality of elements of the reconfigurable intelligent surface;

receive a message that indicates an element grouping type for the reconfigurable intelligent surface, the element grouping type selected from the one or more element grouping types indicated via the capability message and a set of resources allocated for reflection of one or more signals using the element grouping type; and

operate, during the set of resources, in accordance with the element grouping type indicated via the message.
The apparatus of claim 1, wherein the instructions are further executable by the processor to cause the apparatus to:

receive a second message that indicates a group-based beamforming weight and a corresponding second element grouping type to be applied for subsequent operations by the reconfigurable intelligent surface, wherein the group-based beamforming weight is based at least in part on operations by the reconfigurable intelligent surface during the set of resources, and wherein the group-based beamforming weight comprises a plurality of reflection coefficients each associated with a respective element group of a set of one or more element groups associated with the second element grouping type; and

operate, during a second set of resources that is after the set of resources in time, in accordance with the group-based beamforming weight and the corresponding second element grouping type indicated via the second message.
The apparatus of claim 2, wherein the instructions to receive the second message are executable by the processor to cause the apparatus to:

receive, via the second message, an indication of an index of the second element grouping type from among a set of indices associated with the one or more element grouping types indicated via the capability message.
The apparatus of claim 2, wherein the instructions to receive the second message are executable by the processor to cause the apparatus to:

receive, via the second message, an indication of an identifier of a resource from among the set of resources, wherein the group-based beamforming weight and the second element grouping type are based at least in part on the identified resource.
The apparatus of claim 1, wherein the instructions to transmit the capability message are executable by the processor to cause the apparatus to:

transmit, for each element grouping type of the one or more element grouping types supported by the reconfigurable intelligent surface, an indication of a quantity of element groups associated with the respective element grouping type, wherein a quantity of elements included in each element group of the quantity of element groups is based at least in part on a total quantity of elements of the plurality of elements of the reconfigurable intelligent surface and the quantity of element groups, and wherein the quantity of elements included in each element group is the same.
The apparatus of claim 1, wherein the instructions to transmit the capability message are executable by the processor to cause the apparatus to:

transmit, for each element grouping type of the one or more element grouping types supported by the reconfigurable intelligent surface, an indication of a quantity of element groups associated with the respective element grouping type and a quantity of elements included in each element group of the quantity of element groups, wherein the quantity of elements in each element group is the same or different.
The apparatus of claim 1, wherein the instructions to transmit the capability message are executable by the processor to cause the apparatus to:

transmit, for each element grouping type of the one or more element grouping types supported by the reconfigurable intelligent surface, an indication of a total quantity of elements of the plurality of elements of the reconfigurable intelligent surface, a quantity of element groups associated with the respective element grouping type, and a ratio associated with each element group of the quantity of element groups, wherein a quantity of elements included in each element group is based at least in part on a product of a respective ratio associated with the element group and the total quantity of elements of the reconfigurable intelligent surface.
The apparatus of claim 1, wherein the instructions to receive the message are executable by the processor to cause the apparatus to:

receive, via the message, an index of the element grouping type from among the one or more element grouping types indicated via the capability message, wherein the element grouping type is selected from among the one or more element grouping types based at least in part on a quantity of resources included in the set of resources allocated for the reflection of the one or more signals, and wherein the element grouping type is associated with a first quantity of element groups;

receive, via the message, an indication of an expanding factor associated with the element grouping type, the expanding factor comprising a number greater than or equal to one, wherein the expanding factor is based at least in part on the quantity of resources; and

operate using a second quantity of element groups of the reconfigurable intelligent surface in accordance with the element grouping type and the expanding factor, wherein the second quantity is based at least in part on a ratio of the first quantity of element groups associated with the element grouping type and the expanding factor.
The apparatus of claim 1, wherein the message indicates a pattern for alternating between a quantity of element groups associated with the element grouping type, and wherein the instructions to operate in accordance with the element grouping type are executable by the processor to cause the apparatus to:

activate, during each resource of the set of resources in accordance with the pattern, a respective element group of the quantity of element groups associated with the element grouping type, wherein a quantity of resources included in the set of resources is the same as the quantity of element groups, and wherein activating the respective element group of the reconfigurable intelligent surface during each resource is based at least in part on the message indicating a per-element on-off channel estimation type.
The apparatus of claim 1, wherein the message indicates a pattern for alternating between a quantity of element groups associated with the element grouping type, and wherein the instructions to operate in accordance with the element grouping type are executable by the processor to cause the apparatus to:

activate, during each resource of the set of resources in accordance with the pattern, the quantity of element groups of the reconfigurable intelligent surface; and

apply, during each resource of the set of resources in accordance with the pattern, a respective reflection coefficient from among a set of candidate reflection coefficients to each element group of the quantity of element groups, wherein applying the respective reflection coefficients is based at least in part on the message indicating a least squared channel estimation type or a compressive sensing channel estimation type.
The apparatus of claim 10, wherein the instructions are further executable by the processor to cause the apparatus to:

generate, during each resource of the set of resources, a respective group-based beamforming weight based at least in part on applying one or more respective reflection coefficients to the quantity of element groups.
The apparatus of claim 1, wherein the instructions to operate in accordance with the element grouping type are executable by the processor to cause the apparatus to:

reflect a set of one or more signals during the set of resources in accordance with the element grouping type.
The apparatus of claim 1, wherein the instructions to transmit the capability message and receive the message are executable by the processor to cause the apparatus to:

transmit, using a controller of the reconfigurable intelligent surface, the capability message; and

receive, using the controller of the reconfigurable intelligent surface, the message.
An apparatus for wireless communication at a network entity, comprising:

a processor;

memory coupled with the processor; and

instructions stored in the memory and executable by the processor to cause the apparatus to:

receive a capability message that indicates one or more element grouping types supported by a reconfigurable intelligent surface, wherein each of the one or more element grouping types corresponds to a respective pattern for grouping a plurality of elements of the reconfigurable intelligent surface;

transmit a message that indicates an element grouping type for the reconfigurable intelligent surface, the element grouping type selected from the one or more element grouping types indicated via the capability message and a set of resources allocated for reflection of one or more signals using the element grouping type; and

transmit the one or more signals during the set of resources.
The apparatus of claim 14, wherein the instructions are further executable by the processor to cause the apparatus to:

receive, based at least in part on the one or more signals, a channel state information report that indicates a group-based beamforming weight, wherein the group-based beamforming weight is based at least in part on operations by the reconfigurable intelligent surface during the set of resources, and wherein the group-based beamforming weight comprises a plurality of reflection coefficients each associated with a respective element group of a set of one or more element groups of the reconfigurable intelligent surface; and

transmit, based at least in part on the channel state information report, a second message that indicates the group-based beamforming weight and a corresponding second element grouping type to be applied for subsequent operations by the reconfigurable intelligent surface.
The apparatus of claim 15, wherein the instructions to transmit the second message are executable by the processor to cause the apparatus to:

transmit, via the second message, an indication of an index of the second element grouping type from among a set of indices associated with the one or more element grouping types indicated via the capability message.
The apparatus of claim 15, wherein the instructions to transmit the second message are executable by the processor to cause the apparatus to:

transmit, via the second message, an indication of an identifier of a resource from among the set of resources, wherein the group-based beamforming weight and the second element grouping type are based at least in part on the identified resource.
The apparatus of claim 14, wherein the instructions to receive the capability message are executable by the processor to cause the apparatus to:

receive, for each element grouping type of the one or more element grouping types supported by the reconfigurable intelligent surface, information that indicates a quantity of element groups associated with the respective element grouping type and a quantity of elements included in each element group of the one or more element groups.
The apparatus of claim 14, wherein the instructions to transmit the message are executable by the processor to cause the apparatus to:

transmit, via the message, an index of the element grouping type from among the one or more element grouping types indicated via the capability message, wherein the element grouping type is based at least in part on a quantity of resources included in the set of resources allocated for the reflection of the one or more signals, and wherein the element grouping type is associated with a first quantity of element groups; and

transmit, via the message, an indication of an expanding factor associated with the element grouping type, the expanding factor comprising a number greater than or equal to one, wherein the expanding factor is based at least in part on the quantity of resources, and wherein a second quantity of element groups for operations by the reconfigurable intelligent surface is based at least in part on a ratio of the first quantity of element groups associated with the element grouping type and the expanding factor.
The apparatus of claim 14, wherein the instructions to transmit the message are executable by the processor to cause the apparatus to:

transmit, via the message, an indication of a pattern for alternating, by the reconfigurable intelligent surface during the set of resources, between a quantity of element groups of the plurality of elements of the reconfigurable intelligent surface associated with the element grouping type and between corresponding reflection coefficients, wherein the pattern is based at least in part on a channel estimation type associated with the one or more signals.
The apparatus of claim 14, wherein the instructions are further executable by the processor to cause the apparatus to:

transmit a second message that indicates a type of channel estimation associated with the one or more signals and a quantity of element groups that is associated with the element grouping type for the reconfigurable intelligent surface, wherein the type of channel estimation comprises a per-element on-off channel estimation type, a least squared channel estimation type, or a compressive sensing channel estimation type.
The apparatus of claim 14, wherein the instructions to transmit the one or more signals are executable by the processor to cause the apparatus to:

transmit the one or more signals for reflection by the reconfigurable intelligent surface to a user equipment (UE) in accordance with the element grouping type.
An apparatus for wireless communication at a user equipment (UE) , comprising:

a processor;

memory in electronic communication with the processor; and

instructions stored in the memory, wherein the instructions are executable by the processor to:

receive a message that indicates an element grouping type for operations by a reconfigurable intelligent surface during a set of resources, wherein the reconfigurable intelligent surface comprises a plurality of elements that support reflection of wireless signals, and wherein the element grouping type corresponds to a respective pattern for grouping the plurality of elements of the reconfigurable intelligent surface into one or more element groups;

receive one or more signals during the set of resources, wherein the one or more signals are at least partially reflected by the reconfigurable intelligent surface in accordance with the element grouping type; and

transmit a channel state information report that indicates a plurality of reflection coefficients based at least in part on measurements of the one or more signals, wherein each reflection coefficient of the plurality of reflection coefficients corresponds to a respective group of the one or more element groups of the plurality of elements of the reconfigurable intelligent surface.
The apparatus of claim 23, wherein the instructions to receive the message are executable by the processor to cause the apparatus to:

receive, via the message, an indication of a quantity of element groups included in the one or more element groups of the reconfigurable intelligent surface, a quantity of elements included in each group of the one or more element groups, or both.
The apparatus of claim 23, wherein the instructions are further executable by the processor to cause the apparatus to:

estimate a channel based at least in part on the measurements of the one or more signals; and

determine a group-based beamforming weight associated with the reconfigurable intelligent surface based at least in part on the estimated channel, wherein the group-based beamforming weight comprises the plurality of reflection coefficients, and wherein transmitting the channel state information report is based at least in part on determining the group-based beamforming weight.
The apparatus of claim 25, wherein the instructions to estimate the channel are executable by the processor to cause the apparatus to:

estimate the channel in accordance with a channel estimation type selected from one of a per-element on-off channel estimation type, a least squared channel estimation type, or a compressive sensing channel estimation type.
The apparatus of claim 23, wherein the instructions are further executable by the processor to cause the apparatus to:

receive, during a second set of resources that is after the set of resources in time, one or more second signals that are at least partially reflected by the reconfigurable intelligent surface in accordance with the plurality of reflection coefficients indicated via the channel state information report.
A method for wireless communication at a reconfigurable intelligent surface, comprising:

transmitting a capability message that indicates one or more element grouping types supported by the reconfigurable intelligent surface, wherein each of the one or more element grouping types corresponds to a respective pattern for grouping a plurality of elements of the reconfigurable intelligent surface;

receiving a message that indicates an element grouping type for the reconfigurable intelligent surface, the element grouping type selected from the one or more element grouping types indicated via the capability message and a set of resources allocated for reflection of one or more signals using the element grouping type; and

operating, during the set of resources, in accordance with the element grouping type indicated via the message.
The method of claim 28, further comprising:

receiving a second message that indicates a group-based beamforming weight and a corresponding second element grouping type to be applied for subsequent operations by the reconfigurable intelligent surface, wherein the group-based beamforming weight is based at least in part on operations by the reconfigurable intelligent surface during the set of resources, and wherein the group-based beamforming weight comprises a plurality of reflection coefficients each associated with a respective element group of a set of one or more element groups associated with the second element grouping type; and

operating, during a second set of resources that is after the set of resources in time, in accordance with the group-based beamforming weight and the corresponding second element grouping type indicated via the second message.
The method of claim 28, wherein transmitting the capability message comprises:

transmitting, for each element grouping type of the one or more element grouping types supported by the reconfigurable intelligent surface, an indication of a quantity of element groups associated with the respective element grouping type, wherein a quantity of elements included in each element group of the quantity of element groups is based at least in part on a total quantity of elements of the plurality of elements of the reconfigurable intelligent surface and the quantity of element groups, and wherein the quantity of elements included in each element group is the same.