WO2024152555A1

WO2024152555A1 - Method and apparatus for pssch transmission in a psfch slot over an unlicensed spectrum

Info

Publication number: WO2024152555A1
Application number: PCT/CN2023/112622
Authority: WO
Inventors: Haipeng Lei; Xiaodong Yu; Zhennian SUN; Xin Guo
Original assignee: Lenovo (Beijing) Limited
Priority date: 2023-08-11
Filing date: 2023-08-11
Publication date: 2024-07-25
Also published as: WO2024152555A9

Abstract

Embodiments of the present disclosure relate to method and apparatus for PSSCH transmission in a PSFCH slot over an unlicensed spectrum. According to some embodiments of the disclosure, a first UE may: receive, from a second UE, an SCI format for scheduling a PSSCH in a slot, wherein the SCI format includes an indicator indicating whether the PSSCH is transmitted by the second UE in a first plurality of symbols in the slot, wherein the first plurality of symbols includes at least one symbol reserved for PSFCH transmission; receive, from the second UE, the PSSCH in a second plurality of symbols in the slot according to the SCI format; and receive, from the second UE, the PSSCH in the first plurality of symbols in the slot in response to the indicator indicating that the PSSCH is transmitted by the second UE in the first plurality of symbols in the slot.

Description

METHOD AND APPARATUS FOR PSSCH TRANSMISSION IN A PSFCH SLOT OVER AN UNLICENSED SPECTRUM

TECHNICAL FIELD

Embodiments of the present disclosure generally relate to wireless communication technology, and more particularly to transmitting a physical sidelink shared channel (PSSCH) in a physical sidelink feedback channel (PSFCH) over an unlicensed spectrum.

BACKGROUND

A wireless communication system may include one or multiple network communication devices, such as base stations, which may support wireless communication for one or multiple user communication devices, which may be otherwise known as user equipment (UE) , or other suitable terminology. The wireless communication system may support wireless communication with one or multiple user communication devices by utilizing resources of the wireless communication system (e.g., time resources (e.g., symbols, slots, subframes, frames, or the like) or frequency resources (e.g., subcarriers, carriers, or the like) . Additionally, the wireless communication system may support wireless communication across various radio access technologies including third generation (3G) radio access technology, fourth generation (4G) radio access technology, fifth generation (5G) (which is also known as new radio (NR) ) radio access technology, among other suitable radio access technologies beyond 5G (e.g., sixth generation (6G) ) .

A wireless communication system may support sidelink communications, in which devices (e.g., UEs) may communicate with one another directly via a sidelink, rather than being linked through a base station (BS) . The term "sidelink" may refer to a radio link established for communicating among devices (e.g., UEs) , as opposed to communicating via the cellular infrastructure (e.g., uplink and downlink) . Sidelink transmission may be performed on a licensed spectrum or an unlicensed spectrum.

There is a need for handling sidelink transmissions on an unlicensed spectrum.

SUMMARY

An article “a” before an element is unrestricted and understood to refer to “at least one” of those elements or “one or more” of those elements. The terms “a, ” “at least one, ” “one or more, ” and “at least one of one or more” may be interchangeable. 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” or “one or both 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. ” Further, as used herein, including in the claims, a “set” may include one or more elements.

Some embodiments of the present disclosure provide a first UE. The first UE may include at least one memory; and at least one processor coupled with the at least one memory and configured to cause the first UE to: receive, from a second UE, a sidelink control information (SCI) format for scheduling a PSSCH in a slot, wherein the SCI format includes an indicator indicating whether the PSSCH is transmitted by the second UE in a first plurality of symbols in the slot, wherein the first plurality of symbols includes at least one symbol reserved for PSFCH transmission; receive, from the second UE, the PSSCH in a second plurality of symbols in the slot according to the SCI format; and receive, from the second UE, the PSSCH in the first plurality of symbols in the slot in response to the indicator indicating that the PSSCH is transmitted by the second UE in the first plurality of symbols in the slot.

Some embodiments of the present disclosure provide a second UE. The second UE may include at least one memory; and at least one processor coupled with the at least one memory and configured to cause the second UE to: transmit, to a first UE, an SCI format for scheduling a PSSCH in a slot, wherein the SCI format includes an indicator indicating whether the PSSCH is transmitted in a first plurality of symbols in the slot, wherein the first plurality of symbols includes at least one symbol reserved for PSFCH transmission; transmit, to the first UE, the PSSCH in a second plurality of symbols in the slot according to the SCI format; and transmit, to the first UE, the PSSCH in the first plurality of symbols in the slot in response to the indicator indicating that the PSSCH is transmitted in the first plurality of symbols in the slot.

Some embodiments of the present disclosure provide a processor. The processor may include at least one controller coupled with at least one memory and configured to cause the processor to: receive, from a second UE, an SCI format for scheduling a PSSCH in a slot, wherein the SCI format includes an indicator indicating whether the PSSCH is transmitted by the second UE in a first plurality of symbols in the slot, wherein the first plurality of symbols includes at least one symbol reserved for PSFCH transmission; receive, from the second UE, the PSSCH in a second plurality of symbols in the slot according to the SCI format; and receive, from the second UE, the PSSCH in the first plurality of symbols in the slot in response to the indicator indicating that the PSSCH is transmitted by the second UE in the first plurality of symbols in the slot.

Some embodiments of the present disclosure provide a processor. The processor may include at least one controller coupled with at least one memory and configured to cause the processor to: transmit, to a first UE, an SCI format for scheduling a PSSCH in a slot, wherein the SCI format includes an indicator indicating whether the PSSCH is transmitted in a first plurality of symbols in the slot, wherein the first plurality of symbols includes at least one symbol reserved for PSFCH transmission; transmit, to the first UE, the PSSCH in a second plurality of symbols in the slot according to the SCI format; and transmit, to the first UE, the PSSCH in the first plurality of symbols in the slot in response to the indicator indicating that the PSSCH is transmitted in the first plurality of symbols in the slot.

Some embodiments of the present disclosure provide a method for wireless communication. The method may include: receiving, from a second UE, an SCI format for scheduling a PSSCH in a slot, wherein the SCI format includes an indicator indicating whether the PSSCH is transmitted by the second UE in a first plurality of symbols in the slot, wherein the first plurality of symbols includes at least one symbol reserved for PSFCH transmission; receiving, from the second UE, the PSSCH in a second plurality of symbols in the slot according to the SCI format; and receiving, from the second UE, the PSSCH in the first plurality of symbols in the slot in response to the indicator indicating that the PSSCH is transmitted by the second UE in the first plurality of symbols in the slot.

Some embodiments of the present disclosure provide a method for wireless communication. The method may include: transmitting, to a first UE, an SCI format for scheduling a PSSCH in a slot, wherein the SCI format includes an indicator indicating whether the PSSCH is transmitted in a first plurality of symbols in the slot, wherein the first plurality of symbols includes at least one symbol reserved for PSFCH transmission; transmitting, to the first UE, the PSSCH in a second plurality of symbols in the slot according to the SCI format; and transmitting, to the first UE, the PSSCH in the first plurality of symbols in the slot in response to the indicator indicating that the PSSCH is transmitted in the first plurality of symbols in the slot.

Some embodiments of the present disclosure provide an apparatus. According to some embodiments of the present disclosure, the apparatus may include: at least one non-transitory computer-readable medium having stored thereon computer-executable instructions; at least one receiving circuitry; at least one transmitting circuitry; and at least one processor coupled to the at least one non-transitory computer-readable medium, the at least one receiving circuitry and the at least one transmitting circuitry, wherein the at least one non-transitory computer-readable medium and the computer executable instructions may be configured to, with the at least one processor, cause the apparatus to perform a method according to some embodiments of the present disclosure.

BRIEF DESCRIPTION OF THE DRAWINGS

In order to describe the manner in which the advantages and features of the disclosure can be obtained, a description of the disclosure is rendered by reference to specific embodiments thereof, which are illustrated in the appended drawings. These drawings depict only exemplary embodiments of the disclosure and are not therefore to be considered limiting of its scope.

FIG. 1 illustrates a schematic diagram of a wireless communication system in accordance with some embodiments of the present disclosure;

FIG. 2 illustrates exemplary sidelink transmissions in accordance with some embodiments of the present disclosure;

FIGs. 3A-3C and FIGs. 4A-4C illustrate exemplary PSSCH transmissions in PSFCH occasions in accordance with some embodiments of the present disclosure;

FIGs. 5 and 6 illustrate flowcharts of methods for wireless communication in accordance with some embodiments of the present disclosure;

FIG. 7 illustrates a block diagram of an exemplary apparatus in accordance with some embodiments of the present disclosure;

FIG. 8 illustrates an example of a UE in accordance with some embodiments of the present disclosure; and

FIG. 9 illustrates an example of a processor in accordance with some embodiments of the present disclosure.

DETAILED DESCRIPTION

The detailed description of the appended drawings is intended as a description of the preferred embodiments of the present disclosure and is not intended to represent the only form in which the present disclosure may be practiced. It should be understood that the same or equivalent functions may be accomplished by different embodiments that are intended to be encompassed within the spirit and scope of the present disclosure.

Reference will now be made in detail to some embodiments of the present disclosure, examples of which are illustrated in the accompanying drawings. To facilitate understanding, embodiments are provided under a specific network architecture (s) and new service scenarios, such as the 3rd generation partnership project (3GPP) 5G NR or 6G, 3GPP LTE, and so on. It is contemplated that along with the developments of network architectures and new service scenarios, all embodiments in the present disclosure are also applicable to similar technical problems; and moreover, the terminologies recited in the present disclosure may change, which should not affect the principles of the present disclosure.

For sidelink communications on an unlicensed spectrum, a channel occupancy time (COT) may be interrupted by a PSFCH occasion. In some cases, for example, when neither the COT initiator UE nor the responding UE transmits a PSFCH in the PSFCH occasion inside of the COT, there may be a COT interruption by another radio access technology (RAT) over the same unlicensed spectrum. In this disclosure, a responding UE over a shared COT can be a receiving UE, which is the target of a PSCCH or PSSCH transmission of a COT initiator UE. In the case of a unicast from the COT initiator UE, within the same COT, when the source ID and destination ID contained in the COT initiator UE’s SCI match the corresponding destination ID and source ID relating to the same unicast at the receiving UE, this receiving UE is a responding UE to the COT initiator UE. In the case of a groupcast or broadcast, when the destination ID contained in the COT initiator UE’s SCI match a destination ID known at the receiving UE, the receiving UE is a responding UE to the COT initiator UE.

Embodiments of the present disclosure provide solutions to solve the above problem. For example, a PSSCH may be transmitted in such PSFCH occasion to occupy the channel. In addition, an automatic gain control (AGC) problem that may occur is also resolve. By adopting the proposed solutions, spectrum utilization efficiency can be further increased with simple UE implementation.

FIG. 1 illustrates a schematic diagram of wireless communication system 100 in accordance with some embodiments of the present disclosure.

The wireless communication system 100 may include one or more NEs 102 (e.g., one or more BSs) , one or more UEs 104, and a core network (CN) 106. The wireless communication system 100 may support various radio access technologies. In some implementations, the wireless communication system 100 may be a 4G network, such as an LTE network or an LTE-Advanced (LTE-A) network. In some other implementations, the wireless communication system 100 may be a NR network, such as a 5G network, a 5G-Advanced (5G-A) network, or a 5G ultra-wideband (5G-UWB) network. In other implementations, the wireless communication system 100 may be a combination of a 4G network and a 5G network, or other suitable radio access technology including Institute of Electrical and Electronics Engineers (IEEE) 802.11 (Wi-Fi) , IEEE 802.16 (WiMAX) , and IEEE 802.20. The wireless communication system 100 may support radio access technologies beyond 5G, for example, 6G. Additionally, the wireless communication system 100 may support technologies, such as time division multiple access (TDMA) , frequency division multiple access (FDMA) , or code division multiple access (CDMA) , etc.

The one or more NEs 102 may be dispersed throughout a geographic region to form the wireless communication system 100. One or more of the NEs 102 described herein may be or include or may be referred to as a network node, a base station, a network element, a network function, a network entity, a radio access network (RAN) , a NodeB, an eNodeB (eNB) , a next-generation NodeB (gNB) , or other suitable terminology. An NE 102 and a UE 104 may communicate via a communication link, which may be a wireless or wired connection. For example, an NE 102 and a UE 104 may perform wireless communication (e.g., receive signaling, transmit signaling) over a Uu interface.

An NE 102 may provide a geographic coverage area for which the NE 102 may support services for one or more UEs 104 within the geographic coverage area. For example, an NE 102 and a UE 104 may support wireless communication of signals related to services (e.g., voice, video, packet data, messaging, broadcast, etc. ) according to one or multiple radio access technologies. In some implementations, an NE 102 may be moveable, for example, a satellite associated with a non-terrestrial network (NTN) . In some implementations, different geographic coverage areas 112 associated with the same or different radio access technologies may overlap, but the different geographic coverage areas may be associated with a different NE 102.

The one or more UEs 104 may be dispersed throughout a geographic region of the wireless communication system 100. A UE 104 may include or may be referred to as a remote unit, a mobile device, a wireless device, a remote device, a subscriber device, a transmitter device, a receiver device, or some other suitable terminology. In some implementations, the UE 104 may be referred to as a unit, a station, a terminal, or a client, among other examples. Additionally, or alternatively, the UE 104 may be referred to as an Internet-of-Things (IoT) device, an Internet-of-Everything (IoE) device, or machine-type communication (MTC) device, among other examples.

A UE 104 may be able to support wireless communication directly with other UEs 104 over a communication link. For example, a UE 104 may support wireless communication directly with another UE 104 over a device-to-device (D2D) communication link. In some implementations, such as vehicle-to-vehicle (V2V) deployments, vehicle-to-everything (V2X) deployments, or cellular-V2X deployments, the communication link 114 may be referred to as a sidelink. For example, a UE 104 may support wireless communication directly with another UE 104 over a PC5 interface.

An NE 102 may support communication with the CN 106, or with another NE 102, or both. For example, an NE 102 may interface with another NE 102 or the CN 106 through one or more backhaul links (e.g., S1, N2, N3 or another network interface) . In some implementations, the NE 102 may communicate with each other directly. In some other implementations, the NE 102 may communicate with each other or indirectly (e.g., via the CN 106. In some implementations, one or more NEs 102 may include subcomponents, such as an access network entity, which may be an example of an access node controller (ANC) . An ANC may communicate with the one or more UEs 104 through one or more other access network transmission entities, which may be referred to as radio heads, smart radio heads, or transmission-reception points (TRPs) .

The CN 106 may support user authentication, access authorization, tracking, connectivity, and other access, routing, or mobility functions. The CN 106 may be an evolved packet core (EPC) , or a 5G core (5GC) , which may include a control plane entity that manages access and mobility (e.g., a mobility management entity (MME) , an access and mobility management functions (AMF) ) and a 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) ) . In some implementations, the control plane entity may manage non-access stratum (NAS) functions, such as mobility, authentication, and bearer management (e.g., data bearers, signal bearers, etc. ) for the one or more UEs 104 served by the one or more NEs 102 associated with the CN 106.

The CN 106 may communicate with a packet data network over one or more backhaul links (e.g., via an S1, N2, N3, or another network interface) . The packet data network may include an application server. In some implementations, one or more UEs 104 may communicate with the application server. A UE 104 may establish a session (e.g., a protocol data unit (PDU) session, or the like) with the CN 106 via an NE 102. The CN 106 may route traffic (e.g., control information, data, and the like) between the UE 104 and the application server using the established session (e.g., the established PDU session) . The PDU session may be an example of a logical connection between the UE 104 and the CN 106 (e.g., one or more network functions of the CN 106) .

In the wireless communication system 100, the NEs 102 and the UEs 104 may use resources of the wireless communication system 100 (e.g., time resources (e.g., symbols, slots, subframes, frames, or the like) or frequency resources (e.g., subcarriers, carriers) ) to perform various operations (e.g., wireless communication) . In some implementations, the NEs 102 and the UEs 104 may support different resource structures. For example, the NEs 102 and the UEs 104 may support different frame structures. In some implementations, such as in 4G, the NEs 102 and the UEs 104 may support a single frame structure. In some other implementations, such as in 5G and among other suitable radio access technologies, the NEs 102 and the UEs 104 may support various frame structures (i.e., multiple frame structures) . The NEs 102 and the UEs 104 may support various frame structures based on one or more numerologies.

One or more numerologies may be supported in the wireless communication system 100, and a numerology may include a subcarrier spacing and a cyclic prefix. A first numerology (e.g., μ=0) may be associated with a first subcarrier spacing (e.g., 15 kHz) and a normal cyclic prefix. In some implementations, the first numerology (e.g., μ=0) associated with the first subcarrier spacing (e.g., 15 kHz) may utilize one slot per subframe. A second numerology (e.g., μ=1) may be associated with a second subcarrier spacing (e.g., 30 kHz) and a normal cyclic prefix. A third numerology (e.g., μ=2) may be associated with a third subcarrier spacing (e.g., 60 kHz) and a normal cyclic prefix or an extended cyclic prefix. A fourth numerology (e.g., μ=3) may be associated with a fourth subcarrier spacing (e.g., 120 kHz) and a normal cyclic prefix. A fifth numerology (e.g., μ=4) may be associated with a fifth subcarrier spacing (e.g., 240 kHz) and a normal cyclic prefix.

A time interval of a resource (e.g., a communication resource) may be organized according to frames (also referred to as radio frames) . Each frame may have a duration, for example, a 10 millisecond (ms) duration. In some implementations, each frame may include multiple subframes. For example, each frame may include 10 subframes, and each subframe may have a duration, for example, a 1 ms duration. In some implementations, each frame may have the same duration. In some implementations, each subframe of a frame may have the same duration.

Additionally or alternatively, a time interval of a resource (e.g., a communication resource) may be organized according to slots. For example, a subframe may include a number (e.g., quantity) of slots. The number of slots in each subframe may also depend on the one or more numerologies supported in the wireless communication system 100. For instance, the first, second, third, fourth, and fifth numerologies (i.e., μ=0, μ=1, μ=2, μ=3, μ=4) associated with respective subcarrier spacings of 15 kHz, 30 kHz, 60 kHz, 120 kHz, and 240 kHz may utilize a single slot per subframe, two slots per subframe, four slots per subframe, eight slots per subframe, and 16 slots per subframe, respectively. Each slot may include a number (e.g., quantity) of symbols (e.g., orthogonal frequency-division multiplexing (OFDM) symbols) . In some implementations, the number (e.g., quantity) of slots for a subframe may depend on a numerology. For a normal cyclic prefix, a slot may include 14 symbols. For an extended cyclic prefix (e.g., applicable for 60 kHz subcarrier spacing) , a slot may include 12 symbols. The relationship between the number of symbols per slot, the number of slots per subframe, and the number of slots per frame for a normal cyclic prefix and an extended cyclic prefix may depend on a numerology. It should be understood that reference to a first numerology (e.g., μ=0) associated with a first subcarrier spacing (e.g., 15 kHz) may be used interchangeably between subframes and slots.

In the wireless communication system 100, an electromagnetic (EM) spectrum may be split, based on frequency or wavelength, into various classes, frequency bands, frequency channels, etc. By way of example, the wireless communication system 100 may support one or multiple operating frequency bands, such as frequency range designations FR1 (410 MHz –7.125 GHz) , FR2 (24.25 GHz –52.6 GHz) , FR3 (7.125 GHz –24.25 GHz) , FR4 (52.6 GHz –114.25 GHz) , FR4a or FR4-1 (52.6 GHz –71 GHz) , and FR5 (114.25 GHz –300 GHz) . In some implementations, the NEs 102 and the UEs 104 may perform wireless communication over one or more of the operating frequency bands. In some implementations, FR1 may be used by the NEs 102 and the UEs 104, among other equipment or devices for cellular communication traffic (e.g., control information, data) . In some implementations, FR2 may be used by the NEs 102 and the UEs 104, among other equipment or devices for short-range, high data rate capabilities.

FR1 may be associated with one or multiple numerologies (e.g., at least three numerologies) . For example, FR1 may be associated with a first numerology (e.g., μ =0) , which includes 15 kHz subcarrier spacing; a second numerology (e.g., μ =1) , which includes 30 kHz subcarrier spacing; and a third numerology (e.g., μ=2) , which includes 60 kHz subcarrier spacing. FR2 may be associated with one or multiple numerologies (e.g., at least 2 numerologies) . For example, FR2 may be associated with a third numerology (e.g., μ=2) , which includes 60 kHz subcarrier spacing; and a fourth numerology (e.g., μ=3) , which includes 120 kHz subcarrier spacing.

A UE 104 may include computing devices, such as desktop computers, laptop computers, personal digital assistants (PDAs) , tablet computers, smart televisions (e.g., televisions connected to the Internet) , set-top boxes, game consoles, security systems (including security cameras) , vehicle on-board computers, network devices (e.g., routers, switches, and modems) , or the like. According to some embodiments of the present disclosure, a UE 104 may include a portable wireless communication device, a smart phone, a cellular telephone, a flip phone, a device having a subscriber identity module, a personal computer, a selective call receiver, or any other device that is capable of sending and receiving communication signals on a wireless network. In some embodiments of the present disclosure, a UE 104 includes wearable devices, such as smart watches, fitness bands, optical head-mounted displays, or the like. Moreover, a UE 104 may be referred to as a subscriber unit, a mobile, a mobile station, a user, a terminal, a mobile terminal, a wireless terminal, a fixed terminal, a subscriber station, a user terminal, or a device, or described using other terminology used in the art. A UE 104 may communicate with an NE 102 (e.g., a BS) via uplink (UL) communication signals. An NE 102 may communicate with a UE 104 via downlink (DL) communication signals.

In some embodiments of the present disclosure, an NE 102 and a UE 104 may communicate over licensed spectrums, whereas in some other embodiments, an NE 102 and a UE 104 may communicate over unlicensed spectrums. The present disclosure is not intended to be limited to the implementation of any particular wireless communication system architecture or protocol.

Sidelink transmission may involve a physical sidelink control channel (PSCCH) and an associated PSSCH, which is scheduled by an SCI format carried on the PSCCH. The SCI and associated PSSCH may be transmitted from a transmitting UE (hereinafter referred to as "Tx UE" ) to a receiving UE (hereinafter referred to as "Rx UE" ) in a unicast manner, to a group of Rx UEs in a groupcast manner, or to Rx UEs within a range in a broadcast manner. The PSSCH may carry data which may require corresponding HARQ-ACK feedback from the Rx UE (s) to the Tx UE. In some embodiments, broadcast transmission may not need HARQ-ACK feedback. In some embodiments, unicast and groupcast transmission may enable HARQ-ACK feedback under some preconditions. The HARQ-ACK feedback for a PSSCH may be carried on a PSFCH.

In some embodiments of the present disclosure, a sidelink transmission may be performed on an unlicensed spectrum. This is advantageous because a sidelink transmission over an unlicensed spectrum can achieve, for example, an increased data rate (s) . In order to achieve fair coexistence between various systems, for example, NR systems (e.g., NR-U systems) and other wireless systems, a channel access procedure, also known as a listen-before-talk (LBT) test, may be performed before communicating on the unlicensed spectrum.

By performing a channel access procedure, a UE can obtain a channel occupancy (CO) and occupy the channel until the maximum channel occupancy time (MCOT) . For example, a UE may initiate a COT by performing a channel access procedure. However, the COT may be interrupted by a PSFCH occasion. For example, assuming that the PSFCH periodicity is 4 slots, when the COT has a duration of more than 4 slots, it will be interrupted twice. This interruption brings various problems. For example, when neither the COT initiator UE nor the responding UE intends to transmit a PSFCH in a PSFCH occasion inside of a COT, there may be a COT interruption by another RAT over the same unlicensed spectrum.

To solve the above problem, in some embodiments, the COT initiator UE or the responding UE may transmit a PSSCH on such PSFCH occasion (hereinafter, "Option 1" ) . In Option 1, either the COT initiator UE or the responding UE transmits a PSSCH on such PSFCH occasion in order to contiguously occupy the channel within the PSFCH occasion. In some other embodiments, the COT initiator UE or the responding UE may transmit a PSFCH-like signal on such PSFCH occasion (hereinafter, "Option 2" ) . In Option 2, either the COT initiator UE or the responding UE transmits a PSFCH-like signal, for example, a PSFCH carrying a dummy bit, simply for occupying the channel within the PSFCH occasion.

However, Option 2 may have some drawbacks. For example, Option 2 implies that multiple symbols in a PSFCH slot (e.g., two symbols for PSFCH transmission and two symbols as gaps before and after the PSFCH transmission) cannot be used for data transmission or control transmission and thus are wasted. In the context of the present disclosure, a PSFCH slot refers to a slot with a PSFCH occasion or a slot with a symbol (s) reserved for PSFCH transmission. Furthermore, since there are two symbols as gaps before and after the PSFCH transmission, a COT loss may happen as the channel is left empty during the gap period. Hence, it is preferred to employ Option 1, as Option 1 can make full use of the four symbols (i.e., the two PSFCH symbols and two gap symbols) and can increase spectrum utilization efficiency.

There are several issues that need to be resolved in order to implement Option 1. One issue is how an Rx UE knows of the PSSCH transmission in the PSFCH occasion. Another issue is related to AGC.

For example, referring to FIG. 2, a UE (denoted as UE #A) may initiate a COT in resource block (RB) set 201 and may determine that neither itself nor its responding UE transmits a PSFCH in the PSFCH slot (i.e., slot n, where symbols 11 and 12 are reserved for PSFCH transmission and symbols 10 and 13 are used as gap symbols) . UE #A may continue its PSSCH transmission until the end of the PSFCH slot. That is, as shown in FIG. 2, UE #A may perform a PSSCH transmission in symbols 0 to 13 of slot n on RB set 201. Another UE (denoted as UE #B) may initiate a COT in RB set 203 and may determine to receive a PSFCH from its responding UE in the PSFCH slot. That is, as shown in FIG. 2, UE #B may receive a PSFCH in symbols 10 and 12 of slot n on RB set 203. In this scenario, an AGC issue may occur on an Rx UE when it receives the PSSCH transmission from UE #A in slot n since the received power of UE #A’s PSSCH transmission in this slot is variable on symbols 0 to 9, 10, 11, 12 and 13. This can easily lead to a decoding failure at the Rx UE side.

Embodiments of the present disclosure provide solutions to solve the above issues. For example, solutions are provided to implement Option 1. In these solutions, an Rx UE would know if a PSSCH is transmitted in the PSFCH occasion. In addition, solutions to the AGC problem are provided. More details on the embodiments of the present disclosure will be illustrated in the following text in combination with the appended drawings.

Embodiments of the present disclosure are discussed in the scenario of a sidelink transmission over an unlicensed spectrum. In some embodiments of the present disclosure, it is assumed for convenience that a slot includes 14 symbols and that symbols 11 and 12 in a PSFCH slot are reserved for PSFCH transmission. Persons skilled in the art would appreciate that these embodiments can be similarly applied to the cases where a slot includes more or fewer symbols or where different symbols are reserved for PSFCH transmission.

In some embodiments of the present disclosure, an SCI format may schedule a PSSCH in a slot. The SCI format may include an indicator indicating whether a PSSCH is transmitted in a plurality of symbols (denoted as symbol set #1) in this slot, wherein symbol set #1 may include at least one symbol reserved for PSFCH transmission. This slot can also be referred to a PSFCH slot. The specific definition of symbol set #1 will be discussed in the following text. Furthermore, as will be described in the following text, the indicator can be implemented in various manners to achieve the above purpose, i.e., informing the Rx UE of a possible PSSCH transmission in a PSFCH occasion. In addition, as will be described in the following text, the indicator and the signal transmitted in symbol set #1 are designed to avoid the AGC problem as described above.

In some embodiments of the present disclosure, a UE (denoted as UE #1A) may initiate a COT in an RB set (denoted as RB set #A) . In the case that UE #1A determines that no PSFCH is to be transmitted in a PSFCH slot (denoted as slot n) on RB set #A (e.g., no PSFCH is to be transmitted in symbol set #1 in slot n on RB set #A) , UE #1A may perform a PSSCH transmission in the PSFCH occasion in slot n (e.g., transmit a PSSCH in symbol set #1 in slot n) on RB set #A to occupy the channel.

For example, UE #1A may transmit, to another UE (denoted as UE #2A) , an SCI format for scheduling a PSSCH (denoted as PSSCH #A) in slot n. The SCI format may include an indicator (denoted as indicator #A) indicating whether PSSCH #A is transmitted in the PSFCH occasion in slot n (e.g., in symbol set #1 in slot n) . As mentioned above, symbol set #1 includes at least one symbol reserved for PSFCH transmission.

In some examples, indicator #A may include at least one bit. For example, indicator #A may include one bit, wherein bit "1" may indicate that PSSCH #Ascheduled by the SCI format is transmitted in symbol set #1 while bit "0" may indicate that PSSCH #A scheduled by the SCI format is not transmitted in symbol set #1; or vice versa.

In response to that UE #1A occupies the full bandwidth of RB set #A for transmitting the PSSCH and UE #1A determines that no PSFCH is to be transmitted in the PSFCH occasion (e.g., no PSFCH is to be transmitted in symbol set #1) in slot n on RB set #A, UE #1A may set indicator #A to indicate that the PSSCH is transmitted in the PSFCH occasion in slot n (e.g., in symbol set #1 in slot n) . In the context of the present disclosure, a UE determining that no PSFCH is to be transmitted in a PSFCH occasion may include the UE determining that neither itself nor its responding UE intends to transmit a PSFCH in the PSFCH occasion. In response to that UE #1A occupies the full bandwidth of RB set #A for transmitting the PSSCH and UE #1A determines that at least one PSFCH is to be transmitted in the PSFCH occasion (e.g., at least one PSFCH is to be transmitted in symbol set #1) in slot n on RB set #A, UE #1A may set indicator #A to indicate that the scheduled PSSCH is not transmitted in the PSFCH occasion in slot n (e.g., in symbol set #1 in slot n) . In the context of the present disclosure, a UE determining that at least one PSFCH is to be transmitted in a PSFCH occasion may include the UE determining that either itself or its responding UE intends to transmit at least one PSFCH in the PSFCH occasion.

In response to that UE #1A occupies a partial bandwidth of RB set #A for transmitting the PSSCH in slot n on RB set #A, UE #1A may set indicator #A to indicate that the PSSCH is not transmitted in the PSFCH occasion in slot n (e.g., in symbol set #1 in slot n) .

UE #1A may act accordingly according to indicator #A. For example, in response to indicator #A indicating a PSSCH is transmitted in symbol set #1 in slot n, UE #1A may transmit, to UE #2A, the PSSCH in symbol set #1 in slot n.

UE #2A may act accordingly according to indicator #A. For example, in response to receiving the SCI format for scheduling PSSCH #A in slot n, UE #2A may receive PSSCH #A according to the SCI format. For example, UE #2A may receive, from UE #1A, PSSCH #A in a plurality of symbols (denoted as symbol set #2) in slot n according to the SCI format. For example, assuming that symbols 11 and 12 in slot n are reserved for PSFCH transmission and symbols 10 and 13 are gap symbols for PSFCH transmission, symbol set #2 may include symbols x to 9 (where symbol x is the sidelink starting symbol in slot n, x≥0) . In response to indicator #A in the SCI format indicating that a PSSCH is transmitted in the PSFCH occasion in slot n (e.g., in symbol set #1 in slot n) , UE #2A may further receive PSSCH #A in the PSFCH occasion in slot n (e.g., in symbol set #1 in slot n) . UE #2A may combine the PSSCH received in symbol set #1 in slot n with the PSSCH received in symbol set #2 in slot n to decode PSSCH #A. In response to indicator #A in the SCI format indicating that a PSSCH is not transmitted in the PSFCH occasion in slot n (e.g., in symbol set #1 in slot n) , UE #2A may not receive any PSSCH transmission in the PSFCH occasion in slot n (e.g., in symbol set #1 in slot n) . In some examples, UE #2A may transmit a PSFCH in the PSFCH occasion in slot n. In some examples, UE #1A may transmit a PSFCH in the PSFCH occasion in slot n.

Symbol set #1 can be implemented in a number of different ways.

In some embodiments, symbol set #1 may include the at least one symbol reserved for PSFCH transmission (e.g., two symbols such as symbols 11 and 12 in a PSFCH slot) , a gap symbol (e.g., symbol 10) before the at least one symbol and a gap symbol (e.g., symbol 13) after the at least one symbol. That is, the last four symbols, i.e., symbol 10 to symbol 13 in a PSFCH slot can be used for data transmission.

For example, in FIG. 3A, symbols 11 and 12 in slot n are reserved for PSFCH transmission and symbols 10 and 13 are gap symbols. A Tx UE may transmit a PSSCH on symbols 0 to 13 in slot n if the SCI scheduling the PSSCH in slot n indicates that a PSSCH is transmitted in symbol set #1 in slot n.

In some embodiments, symbol set #1 may include the at least one symbol reserved for PSFCH transmission (e.g., two symbols such as symbols 11 and 12 in a PSFCH slot) and a gap symbol (e.g., symbol 10) before the at least one symbol. The gap symbol (e.g., symbol 13) after the at least one symbol may be reserved as a gap for performing Tx-to-Rx switching and/or channel access. That is, symbol 10 to symbol 12 in a PSFCH slot can be used for data transmission.

For example, in FIG. 3B, symbols 11 and 12 in slot n are reserved for PSFCH transmission and symbols 10 and 13 are gap symbols. A Tx UE may transmit a PSSCH on symbols 0 to 12 in slot n if the SCI scheduling the PSSCH in slot n indicates that a PSSCH is transmitted in symbol set #1 in slot n.

In some embodiments, symbol set #1 may include the at least one symbol reserved for PSFCH transmission (e.g., two symbols such as symbols 11 and 12 in a PSFCH slot) and include no gap symbol. For example, the gap symbol (e.g., symbol 10) before the at least one symbol and the gap symbol (e.g., symbol 13) after the at least one symbol may be reserved as gaps for performing Tx-to-Rx switching and/or channel access. That is, symbol 11 and symbol 12 in a PSFCH slot can be used for data transmission.

For example, in FIG. 3C, symbols 11 and 12 in slot n are reserved for PSFCH transmission and symbols 10 and 13 are gap symbols. A Tx UE may transmit a PSSCH on symbols 0 to 9, 11 and 12 in slot n if the SCI scheduling the PSSCH in slot n indicates that a PSSCH is transmitted in symbol set #1 in slot n.

PSSCH transmission in symbol set #1 can be implemented in a number of different ways.

In some embodiments, symbol set #1 may include a repetition of one or more starting symbols of symbol set #2. For example, the PSSCH scheduled by the SCI format may end in symbol 9 in a PSFCH slot. Symbol set #2 may include symbols x to 9 in the PSFCH slot (where symbol x is the sidelink starting symbol in slot n, x≥0) . It is assumed that symbol set #1 includes N symbols. The N symbols in symbol set #1 may be a repetition of the first N symbols of symbol set #2. In some examples, the first N symbols of symbol set #2 may exclude the AGC symbol since it may not be necessary to repeat the AGC symbol in the same slot. In some examples, the first N symbols of symbol set #2 may include the AGC symbol for easier implementation. For example, referring to FIG. 3A, symbol set #1 includes symbols 10 to 13 and symbol set #2 includes symbols 0 to 9, where symbol 0 may be the AGC symbol. In some examples, symbols 10 to 13 of slot n may be a repetition of symbols 0 to 3 of slot n. In some other examples, symbols 10 to 13 of slot n may be a repetition of symbols 1 to 4 of slot n. In these embodiments, a UE may combine the PSSCH received in symbol set #1 of slot n with the PSSCH received in symbol set #2 of slot n to decode the corresponding PSSCH.

In some embodiments, symbol set #1 may include a repetition of one or more last symbols of symbol set #2. For example, the PSSCH scheduled by the SCI format may end in symbol 9 in a PSFCH slot. Symbol set #2 may include symbols x to 9 in the PSFCH slot (where symbol x is the sidelink starting symbol in slot n, x≥0) . It is assumed that symbol set #1 includes N symbols. The N symbols in symbol set #1 may be a repetition of the last N symbols of symbol set #2. For example, referring to FIG. 3A, symbol set #1 includes symbols 10 to 13 and symbol set #2 includes symbols 0 to 9. In some examples, symbols 10 to 13 of slot n may be a repetition of symbols 6 to 9 of slot n. In these embodiments, a UE may combine the PSSCH received in symbol set #1 of slot n with the PSSCH received in symbol set #2 of slot n to decode the corresponding PSSCH.

In some embodiments, symbol set #1 may include a repetition of one or more starting symbols of a next slot. It is assumed that symbol set #1 includes N symbols. The N symbols in symbol set #1 may be a repetition of the first N symbols of the next slot. For example, UE #1A may further transmit a PSSCH in the next slot (e.g., slot n+1) . The N symbols in symbol set #1 may be a repetition of the first N symbols of slot n+1. In some examples, the first N symbols of slot n+1 may exclude the AGC symbol since it may not be necessary to repeat the AGC symbol in two consecutive slots. In some examples, the first N symbols of slot n+1 may include the AGC symbol for easier implementation. For example, referring to FIG. 3A, symbol set #1 includes symbols 10 to 13. In some examples, UE #1A may transmit another PSSCH in slot n+1 (not shown in FIG. 3A) , where symbol 0 of slot n+1 may be the AGC symbol. In some examples, symbols 10 to 13 of slot n may be a repetition of symbols 0 to 3 of slot n+1. In some other examples, symbols 10 to 13 of slot n may be a repetition of symbols 1 to 4 of slot n+1. In these embodiments, UE #2A may combine the PSSCH received in symbol set #1 of slot n with the PSSCH received in slot n+1 to decode the corresponding PSSCH.

In some embodiments of the present disclosure, a UE (denoted as UE #1B) may initiate a COT in an RB set (denoted as RB set #B) . In the case that UE #1B determines that no PSFCH is to be transmitted in a PSFCH slot (e.g., slot n) on RB set #B (e.g., no PSFCH is to be transmitted in symbol set #1 in slot n on RB set #B) , UE #1B may perform a PSSCH transmission in the PSFCH occasion in slot n (e.g., transmit a PSSCH in symbol set #1 in slot n) on RB set #B to occupy the channel.

For example, UE #1B may transmit, to another UE (denoted as UE #2B) , an SCI format for scheduling a PSSCH (denoted as PSSCH #B) in slot n. The SCI format include an indicator (denoted as indicator #B) indicating the last symbol for PSSCH #B in slot n. For example, it is assumed that symbols 11 and 12 in a PSFCH slot (e.g., slot n) are reserved for PSFCH transmission and symbols 10 and 13 are gap symbols for PSFCH transmission. When symbol 13 in slot n is used as a gap symbol for Tx-to-Rx switching and/or channel access performing, indicator #B may indicate the index of the last symbol of the scheduled PSSCH is either symbol 9 or symbol 12. When symbol 13 in slot n is used for PSSCH transmission, indicator #B may indicate the index of the last symbol of the scheduled PSSCH is either symbol 9 or symbol 13.

In the case that indicator #B indicates symbol 9, it suggests that PSSCH #B is not transmitted in the PSFCH occasion in slot n (e.g., in symbol set #1 in slot n) . In the case that indicator #B indicates symbol 12 or 13, it suggests that PSSCH #B is transmitted in the PSFCH occasion in slot n (e.g., in symbol set #1 in slot n) . As mentioned above, symbol set #1 includes at least one symbol reserved for PSFCH transmission (e.g., at least one of symbols 11 and 12) .

In some examples, indicator #B may include at least one bit. For example, indicator #B may include one bit, wherein bit "1" may indicate that the index of the last symbol of the scheduled PSSCH is symbol 9 while bit "0" may indicate that the index of the last symbol of the scheduled PSSCH is symbol 12 or 13 (depending on whether symbol 13 can be used for the PSSCH transmission or not) ; or vice versa. For example, indicator #B may include two bits to indicate the index of the last symbol of the scheduled PSSCH being symbol 9, symbol 12 or symbol 13.

In response to that UE #1B occupies the full bandwidth of RB set #B for transmitting the PSSCH and UE #1B determines that no PSFCH is to be transmitted in the PSFCH occasion (e.g., no PSFCH is to be transmitted in symbol set #1) in slot n on RB set #B, UE #1B may set indicator #B to indicate symbol 12 or 13, which suggests that the scheduled PSSCH is transmitted in the PSFCH occasion in slot n (e.g., in symbol set #1 in slot n) . In response to that UE #1B occupies the full bandwidth of RB set #B for transmitting the PSSCH and UE #1B determines that at least one PSFCH is to be transmitted in the PSFCH occasion (e.g., at least one PSFCH is to be transmitted in symbol set #1) in slot n on RB set #B, UE #1B may set indicator #B to indicate symbol 9, which suggests that the scheduled PSSCH is not transmitted in the PSFCH occasion in slot n (e.g., in symbol set #1 in slot n) . In the context of the present disclosure, a UE determining that at least one PSFCH is to be transmitted in a PSFCH occasion may include the UE determining that either itself or its responding UE intends to transmit at least one PSFCH in the PSFCH occasion.

In response to that UE #1B occupies a partial bandwidth of RB set #B for transmitting the PSSCH in slot n on RB set #B, UE #1B may set indicator #B to indicate symbol 9, which suggests that the scheduled PSSCH is not transmitted in the PSFCH occasion in slot n (e.g., in symbol set #1 in slot n) .

UE #1B may act accordingly according to indicator #B. For example, in response to indicator #B indicating the last symbol of the scheduled PSSCH is symbol 12 or 13 (i.e., a PSSCH is transmitted in symbol set #1 in slot n) , UE #1B may transmit, to UE #2B, the PSSCH in symbol set #1 in slot n.

UE #2B may act accordingly according to indicator #B. For example, in response to receiving the SCI format for scheduling PSSCH #B in slot n, UE #2B may receive PSSCH #B according to the SCI format. For example, UE #2B may receive, from UE #1B, PSSCH #B in a plurality of symbols (denoted as symbol set #2') in slot n according to the SCI format. For example, symbol set #2' may include symbols x to 9 (where symbol x is the sidelink starting symbol in slot n, x≥0) . In response to indicator #B in the SCI format indicating symbol 12 or 13, UE #2B may continue to receive PSSCH #B in the PSFCH occasion in slot n (e.g., in symbol set #1 in slot n) . In response to indicator #B in the SCI format indicating symbol 9, UE #2B may not receive any PSSCH transmission in the PSFCH occasion in slot n (e.g., in symbol set #1 in slot n) . In some examples, UE #2B may transmit a PSFCH in the PSFCH occasion in slot n. In some examples, UE #1B may transmit a PSFCH in the PSFCH occasion in slot n.

Symbol set #1 can be implemented in a number of different ways.

For example, in FIG. 4A, symbols 11 and 12 in slot n are reserved for PSFCH transmission and symbols 10 and 13 are gap symbols. A Tx UE may transmit a PSSCH on symbols 0 to 13 in slot n if the SCI scheduling the PSSCH in slot n indicates that the last symbol of the scheduled PSSCH is symbol 13 (i.e., indicating that a PSSCH is transmitted in symbol set #1 in slot n) .

For example, in FIG. 4B, symbols 11 and 12 in slot n are reserved for PSFCH transmission and symbols 10 and 13 are gap symbols. A Tx UE may transmit a PSSCH on symbols 0 to 12 in slot n if the SCI scheduling the PSSCH in slot n indicates that the last symbol of the scheduled PSSCH is symbol 12 (i.e., indicating that a PSSCH is transmitted in symbol set #1 in slot n) .

For example, in FIG. 4C, symbols 11 and 12 in slot n are reserved for PSFCH transmission and symbols 10 and 13 are gap symbols. A Tx UE may transmit a PSSCH on symbols 0 to 9, 11 and 12 in slot n if the SCI scheduling the PSSCH in slot n indicates that the last symbol of the scheduled PSSCH is symbol 12 (i.e., indicating that a PSSCH is transmitted in symbol set #1 in slot n) .

It is assumed that symbol set #1 includes N' symbols and symbol set #2' include M symbols. For example, symbol set #2' may include symbols x to 9 in a PSFCH slot (where symbol x is the sidelink starting symbol in slot n, x≥0) since the PSSCH scheduled by the SCI format may end in symbol 9 in a PSFCH slot.

In some embodiments, both the M symbols in symbol set #2' and the N' symbols in symbol set #1 are used to transmit a transport block (TB) . The first (starting) symbol of the N' symbols in symbol set #1 is used as an AGC symbol (denoted as AGC symbol #1) . For example, the first (starting) symbol of the N' symbols in symbol set #1 is a repetition of the second symbol of the N' symbols in symbol set #1. The first (starting) symbol of the M symbols in symbol set #2' is used as an AGC symbol (denoted as AGC symbol #2) . For example, the first (starting) symbol of the M symbols in symbol set #2' is a repetition of the second symbol of the M symbols in symbol set #2'. For example, the scheduled TB is rate-matched on the M+N' symbols excluding the two AGC symbols (i.e., AGC symbol #1 and AGC symbol #2) .

For example, referring to FIG. 4A, symbol set #1 includes symbols 10 to 13 and symbol set #2' includes symbols 0 to 9. Symbol 0 is AGC symbol #2 and symbol 10 is AGC symbol #1. Referring to FIG. 4B, symbol set #1 includes symbols 10 to 12 and symbol set #2' includes symbols 0 to 9. Symbol 0 is AGC symbol #2 and symbol 10 is AGC symbol #1. Referring to FIG. 4C, symbol set #1 includes symbols 11 and 12 and symbol set #2' includes symbols 0 to 9. Symbol 0 is AGC symbol #2 and symbol 11 is AGC symbol #1.

AGC symbol #1 can be implemented in a number of different ways. For example, AGC symbol #1 carries a signal for AGC. In some embodiments, the signal for AGC may occupy the full symbol duration. That is, the AGC signal occupies the entire symbol with no gap between this AGC symbol and the previous symbol.

In some embodiments, the AGC signal may occupy a partial symbol duration. For example, there is a gap between the AGC signal and the previous symbol. For example, the gap may not be larger than a sensing interval (e.g., a sensing interval for a channel access procedure such as 16μs) . For example, the duration and starting point of the AGC signal may be the same as those of a cyclic prefix extension (CPE) applied to a PSFCH transmission in the current PSFCH occasion (e.g., symbols 11 and 12 in slot n) .

UE #2B may adjust its AGC setting based on AGC symbols (e.g., AGC symbol #1 and AGC symbol #2) . For example, in response to indicator #B in the SCI format indicating symbol 12 or 13, UE #2B may receive the scheduled PSSCH (or scheduled TB) in both symbol set #1 and symbol set #2'. UE #2B may adjust its AGC circuit based on AGC symbol #1 to receive the scheduled PSSCH in symbol set #1. UE #2B may combine the PSSCH received in symbol set #1 in slot n with the PSSCH received in symbol set #2' in slot n to decode the scheduled PSSCH.

FIG. 5 illustrates a flowchart of method 500 for wireless communication in accordance with some embodiments of the present disclosure. Details described in all of the foregoing embodiments of the present disclosure are applicable for the embodiments shown in FIG. 5. In some examples, method 500 may be performed by a UE, for example, UE 105 as described with reference to FIG. 1. In some embodiments, the UE may execute a set of instructions to control the functional elements of the UE to perform the described functions or operations. In some examples, a processor of a UE may cause the UE to perform method 500.

At 511, a first UE may receive, from a second UE, an SCI format for scheduling a PSSCH in a slot, wherein the SCI format includes an indicator indicating whether the PSSCH is transmitted by the second UE in a first plurality of symbols in the slot, wherein the first plurality of symbols includes at least one symbol reserved for PSFCH transmission.

At 513, the first UE may receive, from the second UE, the PSSCH in a second plurality of symbols in the slot according to the SCI format. At 515, the first UE may receive, from the second UE, the PSSCH in the first plurality of symbols in the slot in response to the indicator indicating that the PSSCH is transmitted by the second UE in the first plurality of symbols in the slot.

In some embodiments, the first plurality of symbols includes: a repetition of one or more starting symbols of the second plurality of symbols; a repetition of one or more last symbols of the second plurality of symbols; or a repetition of one or more starting symbols of a next slot.

In some embodiments, the indicator indicates the last symbol for the PSSCH in the slot.

In some embodiments, the first UE may determine that the PSSCH is transmitted in the first plurality of symbols in the slot in response to the indicator indicating a first symbol index. In some embodiments, the first UE may determine that the PSSCH is not transmitted in the first plurality of symbols in the slot in response to the indicator indicating a second symbol index different from the first symbol index.

In some embodiments, the first plurality of symbols and the second plurality of symbols carry a TB, a starting symbol of the first plurality of symbols carries a first signal for AGC, and a starting symbol of the second plurality of symbols carries a second signal for AGC.

In some embodiments, the first signal for AGC occupies: a full symbol duration; a partial symbol duration, wherein a gap between the first signal for AGC and a previous symbol is not larger than a sensing interval; or a partial symbol duration, wherein a duration and a starting point of the first signal for AGC are the same as those of a cyclic prefix extension applied to the PSFCH transmission.

In some embodiments, the first UE may adjust an AGC setting based on the first signal for AGC.

In some embodiments, the first plurality of symbols further includes: a gap symbol before the at least one symbol and a gap symbol after the at least one symbol; or a gap symbol before the at least one symbol.

In some embodiments, the first UE may combine the PSSCH received in the first plurality of symbols with the PSSCH received in the second plurality of symbols to decode the PSSCH.

It should be appreciated by persons skilled in the art that the sequence of the operations in exemplary method 500 may be changed and some of the operations in exemplary method 500 may be eliminated or modified, without departing from the spirit and scope of the disclosure.

FIG. 6 illustrates a flowchart of method 600 for wireless communication in accordance with some embodiments of the present disclosure. Details described in all of the foregoing embodiments of the present disclosure are applicable for the embodiments shown in FIG. 6. In some examples, method 600 may be performed by a UE, for example, UE 106 as described with reference to FIG. 1. In some embodiments, the UE may execute a set of instructions to control the functional elements of the UE to perform the described functions or operations. In some examples, a processor of a UE may cause the UE to perform method 600.

At 611, a second UE may receive, from a second UE, an SCI format for scheduling a PSSCH in a slot, wherein the SCI format includes an indicator indicating whether the PSSCH is transmitted by the second UE in a first plurality of symbols in the slot, wherein the first plurality of symbols includes at least one symbol reserved for PSFCH transmission.

At 613, the second UE may receive, from the second UE, the PSSCH in a second plurality of symbols in the slot according to the SCI format. At 615, the second UE may receive, from the second UE, the PSSCH in the first plurality of symbols in the slot in response to the indicator indicating that the PSSCH is transmitted by the second UE in the first plurality of symbols in the slot.

In some embodiments, the second UE may initiate a COT in an RB set; and perform one or more of the following: setting the indicator to indicate that the PSSCH is transmitted in the first plurality of symbols in the slot in response to that the second UE occupies the full bandwidth of the RB set for transmitting the PSSCH and the second UE determines that no PSFCH is to be transmitted in the first plurality of symbols in the slot on the RB set; and setting the indicator to indicate that the PSSCH is not transmitted in the first plurality of symbols in the slot in response to that the second UE occupies a partial bandwidth of the RB set for transmitting the PSSCH or the second UE determines that a PSFCH is to be transmitted in the first plurality of symbols in the slot on the RB set.

In some embodiments, the second UE may set the indicator as a first symbol index to indicate that the PSSCH is transmitted in the first plurality of symbols in the slot. In some embodiments, the second UE may set the indicator as a second symbol index different from the first symbol index to indicate that the PSSCH is not transmitted in the first plurality of symbols in the slot.

It should be appreciated by persons skilled in the art that the sequence of the operations in exemplary method 600 may be changed and some of the operations in exemplary method 600 may be eliminated or modified, without departing from the spirit and scope of the disclosure.

FIG. 7 illustrates a block diagram of exemplary apparatus 700 according to some embodiments of the present disclosure. As shown in FIG. 7, the apparatus 700 may include at least one processor 706 and at least one transceiver 702 coupled to the processor 706. The apparatus 700 may be a UE.

Although in this figure, elements such as the at least one transceiver 702 and processor 706 are described in the singular, the plural is contemplated unless a limitation to the singular is explicitly stated. In some embodiments of the present disclosure, the transceiver 702 may be divided into two devices, such as a receiving circuitry and a transmitting circuitry. In some embodiments of the present disclosure, the apparatus 700 may further include an input device, a memory, and/or other components.

In some embodiments of the present disclosure, the apparatus 700 may be a UE. The transceiver 702 and the processor 706 may interact with each other so as to perform the operations with respect to the UE described in FIGs. 1-6.

In some embodiments of the present disclosure, the apparatus 700 may further include at least one non-transitory computer-readable medium. For example, in some embodiments of the present disclosure, the non-transitory computer-readable medium may have stored thereon computer-executable instructions to cause the processor 706 to implement the method with respect to the UE as described above. For example, the computer-executable instructions, when executed, cause the processor 706 interacting with transceiver 702 to perform the operations with respect to the UE described in FIGs. 1-6.

FIG. 8 illustrates an example of a UE 800 in accordance with aspects of the present disclosure. The UE 800 may include a processor 802, a memory 804, a controller 806, and a transceiver 808. The processor 802, the memory 804, the controller 806, or the transceiver 808, or various combinations thereof or various components thereof may be examples of means for performing various aspects of the present disclosure as described herein. These components may be coupled (e.g., operatively, communicatively, functionally, electronically, electrically) via one or more interfaces.

The processor 802, the memory 804, the controller 806, or the transceiver 808, or various combinations or components thereof may be implemented in hardware (e.g., circuitry) . The hardware may include a processor, a digital signal processor (DSP) , an application-specific integrated circuit (ASIC) , or other programmable logic device, or any combination thereof configured as or otherwise supporting a means for performing the functions described in the present disclosure.

The processor 802 may include an intelligent hardware device (e.g., a general-purpose processor, a DSP, a CPU, an ASIC, an FPGA, or any combination thereof) . In some implementations, the processor 802 may be configured to operate the memory 804. In some other implementations, the memory 804 may be integrated into the processor 802. The processor 802 may be configured to execute computer-readable instructions stored in the memory 804 to cause the UE 800 to perform various functions of the present disclosure.

The memory 804 may include volatile or non-volatile memory. The memory 804 may store computer-readable, computer-executable code including instructions when executed by the processor 802 cause the UE 800 to perform various functions described herein. The code may be stored in a non-transitory computer-readable medium such as the memory 804 or another type of memory. 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 place to another. A non-transitory storage medium may be any available medium that may be accessed by a general-purpose or special-purpose computer.

In some implementations, the processor 802 and the memory 804 coupled with the processor 802 may be configured to cause the UE 800 to perform one or more of the functions described herein (e.g., executing, by the processor 802, instructions stored in the memory 804) . For example, the processor 802 may support wireless communication at the UE 800 in accordance with examples as disclosed herein.

For example, the UE 800 may be configured to support means for performing the operations as described with respect to FIG. 5. For example, the UE 800 may be configured to support: a means for receiving, from a second UE, an SCI format for scheduling a PSSCH in a slot, wherein the SCI format includes an indicator indicating whether the PSSCH is transmitted by the second UE in a first plurality of symbols in the slot, wherein the first plurality of symbols includes at least one symbol reserved for PSFCH transmission; a means for receiving, from the second UE, the PSSCH in a second plurality of symbols in the slot according to the SCI format; and a means for receiving, from the second UE, the PSSCH in the first plurality of symbols in the slot in response to the indicator indicating that the PSSCH is transmitted by the second UE in the first plurality of symbols in the slot.

For example, the UE 800 may be configured to support means for performing the operations as described with respect to FIG. 6. For example, the UE 800 may be configured to support: a means for transmitting, to a first UE, an SCI format for scheduling a PSSCH in a slot, wherein the SCI format includes an indicator indicating whether the PSSCH is transmitted in a first plurality of symbols in the slot, wherein the first plurality of symbols includes at least one symbol reserved for PSFCH transmission; a means for transmitting, to the first UE, the PSSCH in a second plurality of symbols in the slot according to the SCI format; and a means for transmitting, to the first UE, the PSSCH in the first plurality of symbols in the slot in response to the indicator indicating that the PSSCH is transmitted in the first plurality of symbols in the slot.

The controller 806 may manage input and output signals for the UE 800. The controller 806 may also manage peripherals not integrated into the UE 800. In some implementations, the controller 806 may utilize an operating system such as or other operating systems. In some implementations, the controller 806 may be implemented as part of the processor 802.

In some implementations, the UE 800 may include at least one transceiver 808. In some other implementations, the UE 800 may have more than one transceiver 808. The transceiver 808 may represent a wireless transceiver. The transceiver 808 may include one or more receiver chains 810, one or more transmitter chains 812, or a combination thereof.

A receiver chain 810 may be configured to receive signals (e.g., control information, data, or packets) over a wireless medium. For example, the receiver chain 810 may include one or more antennas for receive the signal over the air or wireless medium. The receiver chain 810 may include at least one amplifier (e.g., a low-noise amplifier (LNA) ) configured to amplify the received signal. The receiver chain 810 may include at least one demodulator configured to demodulate the receive signal and obtain the transmitted data by reversing the modulation technique applied during transmission of the signal. The receiver chain 810 may include at least one decoder for decoding the processing the demodulated signal to receive the transmitted data.

A transmitter chain 812 may be configured to generate and transmit signals (e.g., control information, data, or packets) . The transmitter chain 812 may include at least one modulator for modulating data onto a carrier signal, preparing the signal for transmission over a wireless medium. The at least one modulator may be configured to support one or more techniques such as amplitude modulation (AM) , frequency modulation (FM) , or digital modulation schemes like phase-shift keying (PSK) or quadrature amplitude modulation (QAM) . The transmitter chain 812 may also include at least one power amplifier configured to amplify the modulated signal to an appropriate power level suitable for transmission over the wireless medium. The transmitter chain 812 may also include one or more antennas for transmitting the amplified signal into the air or wireless medium.

It should be appreciated by persons skilled in the art that the components in exemplary UE 800 may be changed, for example, some of the components in exemplary UE 800 may be omitted or modified or a new component (s) may be added to exemplary UE 800, without departing from the spirit and scope of the disclosure. For example, in some embodiments, the UE 800 may not include the controller 806.

FIG. 9 illustrates an example of a processor 900 in accordance with aspects of the present disclosure. The processor 900 may be an example of a processor configured to perform various operations in accordance with examples as described herein. The processor 900 may include a controller 902 configured to perform various operations in accordance with examples as described herein. The processor 900 may optionally include at least one memory 904, which may be, for example, an L1/L2/L3 cache. Additionally, or alternatively, the processor 900 may optionally include one or more arithmetic-logic units (ALUs) 906. One or more of these components may be in electronic communication or otherwise coupled (e.g., operatively, communicatively, functionally, electronically, electrically) via one or more interfaces (e.g., buses) .

The processor 900 may be a processor chipset and include a protocol stack (e.g., a software stack) executed by the processor chipset to perform various operations (e.g., receiving, obtaining, retrieving, transmitting, outputting, forwarding, storing, determining, identifying, accessing, writing, reading) in accordance with examples as described herein. The processor chipset may include one or more cores, one or more caches (e.g., memory local to or included in the processor chipset (e.g., the processor 900) or other memory (e.g., random access memory (RAM) , read-only memory (ROM) , dynamic RAM (DRAM) , synchronous dynamic RAM (SDRAM) , static RAM (SRAM) , ferroelectric RAM (FeRAM) , magnetic RAM (MRAM) , resistive RAM (RRAM) , flash memory, phase change memory (PCM) , and others) .

The controller 902 may be configured to manage and coordinate various operations (e.g., signaling, receiving, obtaining, retrieving, transmitting, outputting, forwarding, storing, determining, identifying, accessing, writing, reading) of the processor 900 to cause the processor 900 to support various operations in accordance with examples as described herein. For example, the controller 902 may operate as a control unit of the processor 900, generating control signals that manage the operation of various components of the processor 900. These control signals include enabling or disabling functional units, selecting data paths, initiating memory access, and coordinating timing of operations.

The controller 902 may be configured to fetch (e.g., obtain, retrieve, receive) instructions from the memory 904 and determine a subsequent instruction (s) to be executed to cause the processor 900 to support various operations in accordance with examples as described herein. The controller 902 may be configured to track memory address of instructions associated with the memory 904. The controller 902 may be configured to decode instructions to determine the operation to be performed and the operands involved. For example, the controller 902 may be configured to interpret the instruction and determine control signals to be output to other components of the processor 900 to cause the processor 900 to support various operations in accordance with examples as described herein. Additionally, or alternatively, the controller 902 may be configured to manage flow of data within the processor 900. The controller 902 may be configured to control transfer of data between registers, ALUs, and other functional units of the processor 900.

The memory 904 may include one or more caches (e.g., memory local to or included in the processor 900 or other memory, such RAM, ROM, DRAM, SDRAM, SRAM, MRAM, flash memory, etc. In some implementations, the memory 904 may reside within or on a processor chipset (e.g., local to the processor 900) . In some other implementations, the memory 904 may reside external to the processor chipset (e.g., remote to the processor 900) .

The memory 904 may store computer-readable, computer-executable code including instructions that, when executed by the processor 900, cause the processor 900 to perform various functions described herein. The code may be stored in a non-transitory computer-readable medium such as system memory or another type of memory. The controller 902 and/or the processor 900 may be configured to execute computer-readable instructions stored in the memory 904 to cause the processor 900 to perform various functions. For example, the processor 900 and/or the controller 902 may be coupled with or to the memory 904, the processor 900, the controller 902, and the memory 904 may be configured to perform various functions described herein. In some examples, the processor 900 may include multiple processors and the memory 904 may include multiple memories. One or more of the multiple processors may be coupled with one or more of the multiple memories, which may, individually or collectively, be configured to perform various functions herein.

The one or more ALUs 906 may be configured to support various operations in accordance with examples as described herein. In some implementations, the one or more ALUs 906 may reside within or on a processor chipset (e.g., the processor 900) . In some other implementations, the one or more ALUs 906 may reside external to the processor chipset (e.g., the processor 900) . One or more ALUs 906 may perform one or more computations such as addition, subtraction, multiplication, and division on data. For example, one or more ALUs 906 may receive input operands and an operation code, which determines an operation to be executed. One or more ALUs 906 be configured with a variety of logical and arithmetic circuits, including adders, subtractors, shifters, and logic gates, to process and manipulate the data according to the operation. Additionally, or alternatively, the one or more ALUs 906 may support logical operations such as AND, OR, exclusive-OR (XOR) , not-OR (NOR) , and not-AND (NAND) , enabling the one or more ALUs 906 to handle conditional operations, comparisons, and bitwise operations.

The processor 900 may support wireless communication in accordance with examples as disclosed herein.

For example, the processor 900 may be configured to support means for performing the operations as described with respect to FIG. 5. For example, the processor 900 may be configured to or operable to support: a means for receiving, from a second UE, an SCI format for scheduling a PSSCH in a slot, wherein the SCI format includes an indicator indicating whether the PSSCH is transmitted by the second UE in a first plurality of symbols in the slot, wherein the first plurality of symbols includes at least one symbol reserved for PSFCH transmission; a means for receiving, from the second UE, the PSSCH in a second plurality of symbols in the slot according to the SCI format; and a means for receiving, from the second UE, the PSSCH in the first plurality of symbols in the slot in response to the indicator indicating that the PSSCH is transmitted by the second UE in the first plurality of symbols in the slot.

For example, the processor 900 may be configured to support means for performing the operations as described with respect to FIG. 6. For example, the processor 900 may be configured to support: a means for transmitting, to a first UE, an SCI format for scheduling a PSSCH in a slot, wherein the SCI format includes an indicator indicating whether the PSSCH is transmitted in a first plurality of symbols in the slot, wherein the first plurality of symbols includes at least one symbol reserved for PSFCH transmission; a means for transmitting, to the first UE, the PSSCH in a second plurality of symbols in the slot according to the SCI format; and a means for transmitting, to the first UE, the PSSCH in the first plurality of symbols in the slot in response to the indicator indicating that the PSSCH is transmitted in the first plurality of symbols in the slot.

It should be appreciated by persons skilled in the art that the components in exemplary processor 900 may be changed, for example, some of the components in exemplary processor 900 may be omitted or modified or a new component (s) may be added to exemplary processor 900, without departing from the spirit and scope of the disclosure. For example, in some embodiments, the processor 900 may not include the ALUs 906.

Those having ordinary skill in the art would understand that the operations or steps of the methods described in connection with the aspects disclosed herein may be embodied directly in hardware, in a software module executed by a processor, or in a combination of the two. A software module may reside in RAM memory, flash memory, ROM memory, EPROM memory, EEPROM memory, registers, a hard disk, a removable disk, a CD-ROM, or any other form of storage medium known in the art. Additionally, in some aspects, the operations or steps of the methods may reside as one or any combination or set of codes and/or instructions on a non-transitory computer-readable medium, which may be incorporated into a computer program product.

While this disclosure has been described with specific embodiments thereof, it is evident that many alternatives, modifications, and variations may be apparent to those skilled in the art. The disclosure is not limited to the examples and designs described herein but is to be accorded with the broadest scope consistent with the principles and novel features disclosed herein. For example, various components of the embodiments may be interchanged, added, or substituted in other embodiments. Also, all of the elements of each figure are not necessary for the operation of the disclosed embodiments. For example, one of ordinary skill in the art of the disclosed embodiments would be enabled to make and use the teachings of the disclosure by simply employing the elements of the independent claims. Accordingly, embodiments of the disclosure as set forth herein are intended to be illustrative, not limiting. Various changes may be made without departing from the spirit and scope of the disclosure.

In this document, the terms "includes, " "including, " or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that includes a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. An element proceeded by "a, " "an, " or the like does not, without more constraints, preclude the existence of additional identical elements in the process, method, article, or apparatus that includes the element. Also, the term "another" is defined as at least a second or more. The term "having" or the like, as used herein, is defined as "including. " Expressions such as "A and/or B" or "at least one of A and B" may include any and all combinations of words enumerated along with the expression. For instance, the expression "A and/or B" or "at least one of A and B" may include A, B, or both A and B. The wording "the first, " "the second" or the like is only used to clearly illustrate the embodiments of the present disclosure, but is not used to limit the substance of the present disclosure.

Claims

A first user equipment (UE) , comprising:

at least one memory; and

at least one processor coupled with the at least one memory and configured to cause the first UE to:

receive, from a second UE, a sidelink control information (SCI) format for scheduling a physical sidelink shared channel (PSSCH) in a slot, wherein the SCI format comprises an indicator indicating whether the PSSCH is transmitted by the second UE in a first plurality of symbols in the slot, wherein the first plurality of symbols comprises at least one symbol reserved for physical sidelink feedback channel (PSFCH) transmission;

receive, from the second UE, the PSSCH in a second plurality of symbols in the slot according to the SCI format; and

receive, from the second UE, the PSSCH in the first plurality of symbols in the slot in response to the indicator indicating that the PSSCH is transmitted by the second UE in the first plurality of symbols in the slot.
The first UE of claim 1, wherein the first plurality of symbols comprises:

a repetition of one or more starting symbols of the second plurality of symbols;

a repetition of one or more last symbols of the second plurality of symbols; or

a repetition of one or more starting symbols of a next slot.
The first UE of claim 1, wherein the indicator indicates the last symbol for the PSSCH in the slot.
The first UE of claim 3, wherein the at least one processor is further configured to cause the first UE to:

determine that the PSSCH is transmitted in the first plurality of symbols in the slot in response to the indicator indicating a first symbol index; or

determine that the PSSCH is not transmitted in the first plurality of symbols in the slot in response to the indicator indicating a second symbol index different from the first symbol index.
The first UE of claim 3, wherein the first plurality of symbols and the second plurality of symbols carry a transport block (TB) , a starting symbol of the first plurality of symbols carries a first signal for automatic gain control (AGC) , and a starting symbol of the second plurality of symbols carries a second signal for AGC.
The first UE of claim 5, wherein the first signal for AGC occupies:

a full symbol duration;

a partial symbol duration, wherein a gap between the first signal for AGC and a previous symbol is not larger than a sensing interval; or

a partial symbol duration, wherein a duration and a starting point of the first signal for AGC are the same as those of a cyclic prefix extension applied to the PSFCH transmission.
The first UE of claim 5, wherein the at least one processor is further configured to cause the first UE to adjust an AGC setting based on the first signal for AGC.
The first UE of any of claims 1-7, wherein the first plurality of symbols further comprises:

a gap symbol before the at least one symbol and a gap symbol after the at least one symbol; or

a gap symbol before the at least one symbol.
The first UE of any of claims 1-7, wherein the at least one processor is further configured to cause the first UE to combine the PSSCH received in the first plurality of symbols with the PSSCH received in the second plurality of symbols to decode the PSSCH.
A second user equipment (UE) , comprising:

at least one memory; and

at least one processor coupled with the at least one memory and configured to cause the second UE to:

transmit, to a first UE, a sidelink control information (SCI) format for scheduling a physical sidelink shared channel (PSSCH) in a slot, wherein the SCI format comprises an indicator indicating whether the PSSCH is transmitted in a first plurality of symbols in the slot, wherein the first plurality of symbols comprises at least one symbol reserved for physical sidelink feedback channel (PSFCH) transmission;

transmit, to the first UE, the PSSCH in a second plurality of symbols in the slot according to the SCI format; and

transmit, to the first UE, the PSSCH in the first plurality of symbols in the slot in response to the indicator indicating that the PSSCH is transmitted in the first plurality of symbols in the slot.
The second UE of claim 10, wherein the at least one processor is further configured to cause the second UE to:

initiate a channel occupancy time (COT) in a resource block (RB) set; and

perform one or more of the following:

setting the indicator to indicate that the PSSCH is transmitted in the first plurality of symbols in the slot in response to that the second UE occupies the full bandwidth of the RB set for transmitting the PSSCH and the second UE determines that no PSFCH is to be transmitted in the first plurality of symbols in the slot on the RB set; and

setting the indicator to indicate that the PSSCH is not transmitted in the first plurality of symbols in the slot in response to that the second UE occupies a partial bandwidth of the RB set for transmitting the PSSCH or the second UE determines that a PSFCH is to be transmitted in the first plurality of symbols in the slot on the RB set.
The second UE of claim 10, wherein the first plurality of symbols comprises:

a repetition of one or more starting symbols of the second plurality of symbols;

a repetition of one or more last symbols of the second plurality of symbols; or

a repetition of one or more starting symbols of a next slot.
The second UE of claim 10, wherein the indicator indicates the last symbol for the PSSCH in the slot.
The second UE of claim 13, wherein the at least one processor is further configured to cause the second UE to:

set the indicator as a first symbol index to indicate that the PSSCH is transmitted in the first plurality of symbols in the slot; or

set the indicator as a second symbol index different from the first symbol index to indicate that the PSSCH is not transmitted in the first plurality of symbols in the slot.
The second UE of claim 13, wherein the first plurality of symbols and the second plurality of symbols carry a transport block (TB) , a starting symbol of the first plurality of symbols carries a first signal for automatic gain control (AGC) , and a starting symbol of the second plurality of symbols carries a second signal for AGC.
The second UE of claim 15, wherein the first signal for AGC occupies:

a full symbol duration;

a partial symbol duration, wherein a gap between the first signal for AGC and a previous symbol is not larger than a sensing interval; or

a partial symbol duration, wherein a duration and a starting point of the first signal for AGC are the same as those of a cyclic prefix extension applied to the PSFCH transmission.
The second UE of any of claims 10-16, wherein the first plurality of symbols further comprises:

a gap symbol before the at least one symbol and a gap symbol after the at least one symbol; or

a gap symbol before the at least one symbol.
A processor, comprising:

at least one controller coupled with at least one memory and configured to cause the processor to:

receive, from a second user equipment (UE) , a sidelink control information (SCI) format for scheduling a physical sidelink shared channel (PSSCH) in a slot, wherein the SCI format comprises an indicator indicating whether the PSSCH is transmitted by the second UE in a first plurality of symbols in the slot, wherein the first plurality of symbols comprises at least one symbol reserved for physical sidelink feedback channel (PSFCH) transmission;

receive, from the second UE, the PSSCH in a second plurality of symbols in the slot according to the SCI format; and

receive, from the second UE, the PSSCH in the first plurality of symbols in the slot in response to the indicator indicating that the PSSCH is transmitted by the second UE in the first plurality of symbols in the slot.
A processor, comprising:

at least one controller coupled with at least one memory and configured to cause the processor to:

transmit, to a first user equipment (UE) , a sidelink control information (SCI) format for scheduling a physical sidelink shared channel (PSSCH) in a slot, wherein the SCI format comprises an indicator indicating whether the PSSCH is transmitted in a first plurality of symbols in the slot, wherein the first plurality of symbols comprises at least one symbol reserved for physical sidelink feedback channel (PSFCH) transmission;

transmit, to the first UE, the PSSCH in a second plurality of symbols in the slot according to the SCI format; and

transmit, to the first UE, the PSSCH in the first plurality of symbols in the slot in response to the indicator indicating that the PSSCH is transmitted in the first plurality of symbols in the slot.