CN116896434A

CN116896434A - Method and apparatus for side link positioning

Info

Publication number: CN116896434A
Application number: CN202310319743.4A
Authority: CN
Inventors: 周昱含; 菲利普·琼·马克·米歇尔·萨托里; 亚瑟·穆罕默德·穆斯塔法·卡梅尔·福亚德
Original assignee: Samsung Electronics Co Ltd
Current assignee: Samsung Electronics Co Ltd
Priority date: 2022-03-31
Filing date: 2023-03-29
Publication date: 2023-10-17

Abstract

Methods and apparatus for side link positioning are disclosed. Methods and apparatus are provided for a User Equipment (UE) to determine a resource pool for receiving Side Link (SL) -Positioning Reference Signals (PRS). The UE receives a slot and determines whether the slot includes resources in the resource pool for SL-PRS. In the case that the slot includes the resources in the resource pool, the UE decodes SL Control Information (SCI) for the slot using a first format for SL-PRS.

Description

Method and apparatus for side link positioning

Cross Reference to Related Applications

The present application claims the priority benefits of U.S. provisional application nos. 63/325,919 and 63/342,476, and the priority benefits of U.S. patent application No. 18/113,456, filed on 3, 2022 and 16, respectively, at 5, 2022, and 23, the disclosures of which are incorporated herein by reference in their entireties as if fully set forth herein.

Technical Field

The present disclosure relates generally to Side Link (SL) positioning. More particularly, the subject matter disclosed herein relates to signal designs for performing SL positioning.

Background

In the 3 rd generation partnership project (3 GPP) release (Rel) -16/17, the positioning of New Radio (NR) links (i.e., NR Uu links) between Universal Mobile Telecommunications System (UMTS) terrestrial radio access networks (UTRAN) and User Equipment (UE) is standardized for cellular links. In 3GPP Rel-18, a positioning protocol is extended for SL. The protocol for performing SL positioning is different from the cellular protocol because there is no central controller on the SL.

To solve this problem, the UE should determine when to transmit a Reference Signal (RS) for positioning, where to obtain various configurations for positioning, and where to report positioning information. Since the resource allocation is distributed (e.g., without a central controller), a mechanism to limit/avoid collisions is needed.

One problem with the above approach is that there is no RS designed for positioning in SL and the Positioning Reference Signal (PRS) must be modified in Uu link to fit SL communication. Reuse of existing RSs in SL, such as e.g. Channel State Information (CSI) -RSs, is not desirable, as PRSs require large bandwidth and are multiplexed by UEs.

Disclosure of Invention

To overcome these problems, a solution is provided for developing SL-PRS in frequency/time domain mode and UE procedures for transmitting and receiving SL-PRS.

The above-described methods improve upon previous methods in that they focus on ensuring that the positioning overhead is low for large scale deployment, thereby ensuring that there is low latency.

In one embodiment, a method for SL positioning is provided, wherein in the method, a UE determines a resource pool for receiving SL-PRS. The UE receives a slot and determines whether the slot includes resources in a resource pool for SL-PRS. In the case that the slot includes resources in the resource pool, the UE decodes SL Control Information (SCI) of the slot using a first format for SL-PRS.

In an embodiment, a method for SL positioning is provided, wherein in the method, a UE determines a resource pool for receiving SL-PRS and receives a positioning slot comprising resources in the resource pool. The positioning slot includes a first resource for one or more symbols of a Physical SL Control Channel (PSCCH) that spans a first subcarrier of the positioning slot. The positioning slot also includes a second resource for the SL-PRS in an area of the positioning slot corresponding to a Physical SL Shared Channel (PSSCH) resource in a non-positioning slot. The second resource spans a bandwidth of the positioning slot.

In an embodiment, a UE is provided, wherein the UE includes a processor and a non-transitory computer-readable storage medium storing instructions. The instructions, when executed, cause the processor to: determining a resource pool for SL-PRS; receiving a time slot; and determining whether the slot includes resources in the pool of resources for the SL-PRS. The instructions also cause the processor to decode a SCI of the slot using a first format for the SL-PRS if the slot includes the resources in the pool of resources.

Drawings

In the following sections, aspects of the subject matter disclosed herein will be described with reference to exemplary embodiments shown in the drawings, in which:

fig. 1 is a diagram illustrating a communication system according to an embodiment;

FIG. 2 is a diagram illustrating Downlink (DL) PRS resources according to an embodiment;

fig. 3 is a diagram illustrating a slot format with feedback according to an embodiment;

fig. 4 is a diagram illustrating a slot format without feedback according to an embodiment;

FIG. 5 is a flow chart illustrating a method for resource selection according to an embodiment;

fig. 6 is a diagram illustrating comb indexes on a first symbol for comb (comb) -4 according to an embodiment;

fig. 7 is a diagram illustrating an RS resource pool when the entire carrier bandwidth is used according to an embodiment;

fig. 8 is a diagram illustrating a slot structure in an RS resource pool according to an embodiment;

fig. 9 is a diagram illustrating a slot structure in an RS resource pool according to another embodiment;

FIG. 10 is a diagram illustrating alternate SL-PRS locations in a slot structure with two UEs, according to an embodiment;

FIG. 11 is a diagram illustrating alternate SL-PRS locations in a slot structure with a single UE, according to an embodiment;

FIG. 12 is a flow chart illustrating a method for receiving SL-PRSs, according to an embodiment;

FIG. 13 is a flow chart illustrating a method for receiving SL-PRSs, according to an embodiment;

FIG. 14 is a flow chart illustrating a method for transmitting SL-PRSs, according to an embodiment;

fig. 15 is a flow chart illustrating a method for resource selection in SL positioning according to an embodiment;

fig. 16 is a diagram illustrating AGC of a slot for SL-PRS according to an embodiment;

fig. 17 is a diagram illustrating AGC in a slot structure according to an embodiment;

fig. 18A is a diagram illustrating a slot structure with PSCCH repetition according to an embodiment;

FIG. 18B is a diagram illustrating a slot structure with SL-PRS repetition according to an embodiment;

fig. 19 is a diagram illustrating a slot structure of a SL-PRS with multiple PSCCH repetitions according to an embodiment;

FIG. 20 is a diagram illustrating a slot structure of SL-PRS with PSCCH interleaving in accordance with an embodiment;

FIG. 21 is a diagram illustrating a slot structure of SL-PRS with PSCCH interleaving and repetition, according to an embodiment;

FIG. 22 is a diagram illustrating a slot structure for SL-PRS without SCI, according to an embodiment;

FIG. 23 is a diagram illustrating a method for receiving SL-PRSs multiplexed with data, according to an embodiment; and

fig. 24 is a block diagram of an electronic device in a network environment according to an embodiment.

Detailed Description

In the following detailed description, numerous specific details are set forth in order to provide a thorough understanding of the present disclosure. However, it will be understood by those skilled in the art that the disclosed aspects may be practiced without these specific details. In other instances, well-known methods, procedures, components, and circuits have not been described in detail so as not to obscure the subject matter disclosed herein.

Reference throughout this specification to "one embodiment" or "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment may be included in at least one embodiment disclosed herein. Thus, the appearances of the phrase "in one embodiment" or "in an embodiment" or "according to one embodiment" (or other phrases having similar meanings) in various places throughout this specification are not necessarily all referring to the same embodiment. Furthermore, the particular features, structures, or characteristics may be combined in any suitable manner in one or more embodiments. In this regard, as used herein, the word "exemplary" means "serving as an example, instance, or illustration. Any embodiment described herein as "exemplary" is not necessarily to be construed as preferred or advantageous over other embodiments. Furthermore, the particular features, structures, or characteristics may be combined in any suitable manner in one or more embodiments. Furthermore, depending on the context discussed herein, singular terms may include corresponding plural forms and plural terms may include corresponding singular forms. Similarly, the hyphenated terms (e.g., "two-dimensional)", "predetermined", "pixel-specific", etc.) may be occasionally used interchangeably with the corresponding non-hyphenated version (e.g., "two-dimensional", "predetermined", "pixel-specific", etc.), and the uppercase items (e.g., "Counter Clock", "Row Select", "pixel (pixel out), etc.) may be used interchangeably with the corresponding non-uppercase version (e.g.," Counter Clock "," Row Select "," pixel "etc.). Such occasional interchangeable uses should not be considered inconsistent with each other.

Furthermore, depending on the context discussed herein, singular terms may include corresponding plural forms and plural terms may include corresponding singular forms. It should also be noted that the various figures (including component figures) shown and discussed herein are for illustrative purposes only and are not drawn to scale. For example, the dimensions of some of the elements may be exaggerated relative to other elements for clarity. Further, where considered appropriate, reference numerals have been repeated among the figures to indicate corresponding elements and/or the like.

The terminology used herein is for the purpose of describing some example embodiments only and is not intended to limit the claimed subject matter. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms "comprises" and/or "comprising," when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof.

It will be understood that when an element or layer is referred to as being "on," "connected to," or "coupled to" another element or layer, it can be directly on, connected or coupled to the other element or layer, or intervening elements or layers may be present. In contrast, when an element is referred to as being "directly on," "directly connected to" or "directly coupled to" another element or layer, there are no intervening elements or layers present. Like numbers refer to like elements throughout. As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed items.

As used herein, the terms "first," "second," and the like, are used as labels for nouns following them, and do not imply any type of ordering (e.g., spatial, temporal, logical, etc.), unless explicitly so defined. Furthermore, the same reference numbers may be used throughout two or more drawings to refer to components, assemblies, blocks, circuits, units, or modules having the same or similar functionality. However, such usage is merely for simplicity of illustration and ease of discussion; it is not intended that the constructional or architectural details of these components or units be the same in all embodiments or that these commonly referenced components/modules be the only way to implement some of the example embodiments disclosed herein.

Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this subject matter belongs. It will be further understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein.

As used herein, the term "module" refers to any combination of software, firmware, and/or hardware configured to provide the functionality described herein in connection with the module. For example, software may be implemented as a software package, code and/or instruction set or instructions, and the term "hardware" as used in any of the embodiments described herein may include, for example, an accessory, a hardwired circuit, a programmable circuit, a state machine circuit, and/or firmware that stores instructions executed by the programmable circuit, either alone or in any combination. Modules may be implemented collectively or individually as circuitry forming part of a larger system, such as, but not limited to, an Integrated Circuit (IC), a system-on-a-chip (SoC), an accessory, and the like.

Fig. 1 is a diagram illustrating a communication system according to an embodiment. In the architecture shown in fig. 1, the control path 102 may enable transmission of control information through a network established between a base station or gNode B (gNB) 104, a first UE 106, and a second UE 108. The data path 110 may enable transmission of data (and some control information) on SL between the first UE 106 and the second UE 108. The control path 102 and the data path 110 may be on the same frequency or may be on different frequencies.

The Rel-16 design of PRS can be reused for SL positioning. In particular, sequences of PRSs may be generated from gold sequences and mapped to Quadrature Phase Shift Keying (QPSK) constellation points and may support at least 4096 different sequence Identifiers (IDs). Furthermore, the Resource Element (RE) pattern of the downlink DL PRS may follow a comb structure with a greater number of different densities (e.g., 1, 2, 3, 4, 6, or 12) per Physical Resource Block (PRB). The bandwidth of PRS may be configurable. The RE patterns staggered in time and frequency may be used to achieve an efficient comb-1 structure at the receiver (e.g., UE).

The PRS sequence as a QPSK symbol can be written as the following equation (1):

wherein the pseudo-random sequence c (i) is a gold sequence of length 31. Length M _PN The output sequence c (n) of (wherein, n=0, 1, M _PN -1) can be defined by the following equation (2):

wherein N is _C =1600 and first m sequence x ₁ (n) available x ₁ (0)＝1,x ₁ (n) =0, n=1, 2,..30. Second m-sequence x ₂ Initialization of (n) may be performed byExpressed by the following equation (3):

wherein,,is slot number, DL PRS sequence->Given by higher layer parameters, and/is the Orthogonal Frequency Division Multiplexing (OFDM) symbol within the slot to which the sequence is mapped.

For each DL PRS resource configured, when the condition is satisfied, the UE may assume the sequence r (m) by a factor β according to the following equation (4) _PRS Scaling and mapping to resource elements (k, l) _p，μ ：

RE (k, l) as a first condition _p，μ Within the resource blocks occupied by DL PRS resources for which the UE is configured. As a second condition, the symbol i is not used by the serving cell for DL PRS transmitted from the serving cell or for any Synchronization Signal (SS) and physical broadcast channel (SS/PBCH) block indicated by higher layer parameters for DL PRS transmitted from the non-serving cell. As a third condition, DL PRSs are transmitted in some specific slots indicated by higher layer parameters. In addition, in the case of the optical fiber,is the first symbol of DL PRS within a slot and is given by higher layer parameters. Size L of DL PRS resources in time domain _PRS E {2,4,6, 12} is given by higher layer parameters. Comb size->Given by higher layer parameters. Resource element offsetGiven by higher layer parameters. The parameter k' is given in Table 1, table 1 shows the values asThe frequency offset k' of the function of (c).

The reference point for=0 is the position of point a of the positioning frequency layer where the DLPRS resources are configured, where point a is given by higher layer parameters.

TABLE 1

FIG. 2 is a diagram illustrating a target according to an embodimentDL PRS resource allocation. Specifically, when L _PRS =12 and->At +.> AndPRS resources 202 are shown in each of (a).

SL physical channels correspond to a set of REs carrying information originating from higher layers. The PSSCH can carry second stage SCI and SL data payloads. The Physical SL Broadcast Channel (PSBCH) may be identical to the Physical Broadcast Channel (PBCH) in Uu link. The PSCCH may carry a first stage SCI. The Physical SL Feedback Channel (PSFCH) may carry 1-bit hybrid automatic repeat request (HARQ) Acknowledgement (ACK) feedback.

SL physical signals correspond to a set of REs used by the physical layer, but do not carry information originating from higher layers. The demodulation reference signal (DM-RS) is a SL signal for PSCCH, PSSCH and PSBCH. The CSI-RS may be used for CSI measurement on SL. The phase tracking reference signal (PT-RS) may be used for frequency range 2 (FR 2) phase noise compensation. The SL master synchronization signal (S-PSS) may be used for synchronization on SL. The SL secondary synchronization signal (S-SSS) may be used for synchronization on SL.

In NR SL, a self-contained approach may be considered whereby each slot contains control, data, and in some cases feedback. A conventional NR SL slot consists of 14 OFDM symbols. However, SL may also be configured/preconfigured to occupy less than 14 symbols in a slot.

SCI in NR internet of vehicles (V2X, vehicle to everything) can be sent in two phases. The first stage SCI (i.e., SCI format 1-a) carried on the PSCCH may contain information to implement the sensing operation, as well as a resource allocation field for the scheduling of the PSSCH and the second stage SCI. The second stage SCI (i.e., SCI format 2-a or SCI format 2-B) may be transmitted in the PSSCH resources and may be associated with PSSCH DMRS, where the PSSCH DMRS contains information for decoding the PSSCH.

The PSCCH and PSSCH may be multiplexed in time and frequency within the same slot. Depending on whether feedback is configured for a given slot, different slot formats may exist.

Fig. 3 is a diagram illustrating a slot structure with feedback resources according to an embodiment. The slot structure is shown with PSSCH 302, PSSCH DMRS, PSCCH 306, PSFCH 308, gap symbols 310, and null resources 312. The first symbol 314 in the subchannel 316 is a copy of the second symbol.

Fig. 4 is a diagram illustrating a slot structure without feedback resources according to an embodiment. The slot structure is shown with pschs 402, PSSCH DMRS, 404, PSCCHs 406 and gap symbols 410. The first symbol 414 in subchannel 416 is a copy of the second symbol.

For both slot structures, the first symbols 314 and 414 may be repeated for Automatic Gain Control (AGC) and the last symbol of the slot may be left in the gap for transmit (Tx)/receive (Rx) switching. The first stage SCI may be carried in PSCCHs 306 and 406 of 2 or 3 symbols with SCI format 1-a. The number of PSCCH symbols may be explicitly configured/preconfigured per Tx/Rx resource pool by the higher layer parameter sl-timeresource scch. The lowest RB of the PSCCH is the same as the lowest RB of the corresponding pscsch. In the frequency domain, the number of RBs in the PSCCH may be preconfigured and not larger than the size of one subchannel. Here, if the UE uses a plurality of consecutive subchannels for SL transmission within a slot, the PSCCH may exist only in the first subchannel.

SL transport channels carrying Transport Blocks (TBs) for data transmitted on the SL and the second stage SCI may be carried on the PSSCH. The resources to transmit the PSSCH may be scheduled or configured by the gNB (i.e., mode 1) or determined by a sensing procedure conducted autonomously by the transmission (i.e., mode 2).

Feedback (as shown in fig. 3) may be carried on the PSFCH 308. The channel may be used to transmit feedback information from the Rx UE to the Tx UE. It can be used for unicast and multicast option 2/1. In case of unicast and multicast option 2, the PSFCH may be used to send an ACK/negative acknowledgement (ACK/NACK), while in case of multicast option 1, the PSFCH may carry only a NACK. For SL feedback, a sequence-based PSFCH format (PSFCH format 0) with one symbol (excluding the AGC training period) may be supported. In PSFCH format 0, ACK/NACK bits are sent over two Zadoff-Chu (ZC) sequences of length 12 (same root but different cyclic shifts), whereby the presence of one sequence indicates ACK and the presence of the other sequence indicates NACK (i.e., the sequences are used in a mutually exclusive manner).

In the UE procedure for determining PSSCH resources in SL resource allocation pattern 2, a higher layer may request the UE to determine a subset of resources from which to select resources for PSSCH/PSCCH transmission. To trigger this procedure, the higher layer may provide parameters for PSSCH/PSCCH transmission in slot n. These parameters may include the resource pool from which the resource will be reported, L1 priority prio _TX Remaining packet delay margin, number of sub-channels to be used for PSSCH/PSCCH transmission in a slot L _subCH Resource reservation interval P optionally in ms _{rsvp_TX} 。

Higher layer parameters affecting the process may include Selection WindowList. For prio _TX Set value of internal parameter T _2min May be set to a corresponding value from the higher layer parameter sl-Selection WindowList.

Another parameter that may affect the process is sl-Thres-RSRP-List. The higher layer parameters are for each combination (p _i ，p _j ) Providing a Reference Signal Received Power (RSRP) threshold, wherein p _i Is the value of the priority field in received SCI Format 1-A, and p _j Is the priority of the transmission of the UE selection resource. For a given call to the procedure, p _j ＝prio _TX 。

Additional higher layer parameters that may affect the procedure include sl-RS-ForSensing, sl-ResourceRes ervePeriodList and sl-sensing Window, where sl-RS-Forsensing selects whether the UE uses PSSCH-RSRP or PSCCH-RSRP measurements. Internal parameter T ₀ May be defined as the number of slots corresponding to sl-sensing window.

Yet another higher layer parameter that may affect the process includes sl-txfacecentagelist. For a given prio _TX The internal parameter X of (2) can be defined as sl-TxPancentrageList (prio) converted from percentage to ratio _TX ). Finally, the parameters may include sl-preemptionEnable, where if sl-preemptionEnable is provided and is not equal to "enable", then the internal parameter prio _pre May be set to a parameter sl-PreemptionEnable provided by a higher layer.

If the resource reservation interval P _{rsvp_TX} Is provided, then the resource reservation interval P _{rsvp_TX} Can be converted from units of ms to units of logical time slots, thusRepresenting a set of timeslots that may belong to the SL resource pool.

Fig. 5 is a diagram illustrating a method for mode 2 resource selection according to an embodiment. At 502, a selection window may be set. Candidate single slot resource R for transmission _x，y Can be defined as being in time slotsL with sub-channel x+j in _subCH A set of consecutive sub-channels, where j=0,.. _subCH -1. The UE may assume that at time interval [ n+t ] ₁ ，n+T ₂ ]L included in corresponding resource pool _subCH Any set of consecutive subchannels corresponds to a candidate single-slot resource, where for T ₁ Is selected depending on the value of T.ltoreq.T at 0 ₁ ≤T _proc，1 UE implementation below, and wherein T _proc，1 Defined by time slots. If T _2mon Shorter than the remaining packet delay margin (in slots), then T ₂ Depending on the UE implementation, it is subject to T _2min ≤T ₂ And less than or equal to the residual packet allowance (taking time slot as a unit). Otherwise, T is taken ₂ Set as the remaining packet delay margin (in slots). The total number of candidate single-slot resources is defined by M _total And (3) representing.

At 504, a sensing window may be set and the time slot may be monitored by decoding the PSCCH and measuring RSRP. The sensing window may be defined by a slot range n-T ₀ ，n-T _proc，0 ) Definition, wherein T ₀ Is defined above, and T _proc，0 Is defined in terms of time slots. In addition to those slots in which its own transmissions occur, the UE may monitor slots that may belong to the SL resource pool within the sensing window. The UE may perform subsequent steps based on the decoded PSCCH and the measured RSRP in these slots.

At 506, a threshold may be set according to the priority value. Internal parameter Th (p) _i ，p _j ) Can be set to a corresponding value of RSRP threshold indicated by the ith field in the sl-Thres-RSRP-List, where i=p _i +(p _j -1)*8。

At 508, the initial set S may be for _A Initialization is performed to include all candidate single slot resources.

At 510, if restricted, the UE may exclude resources. Specifically, the UE may be from set S if the UE satisfies all of the following conditions ₄ Excluding any candidate single slot resources R _x，y . First, at 504, the UE has not yet monitored the slotSecond, any periodicity value allowed for higher layer parameter reservationperiodic and +_in time slot >A third condition of 512 may be satisfied assuming SCI format 0-1, where SCI format 0-1 is assumed to have a "resource reservation period" field set to the periodicity value and indicating all sub-channels of the resource pool in the slot.

At 512, if resources are occupied by UEs with higher priority and RSRP > Th, the UE may exclude these resources. Specifically, the UE may be from set S if the UE satisfies all of the following conditions _A Excluding any candidate single slot resources R _x，y . First, the UE is in a slotSCI format 0-1, and the "resource reservation period" field (if present) and "priority" field in the received SCI format 0-1 respectively indicate the value P _{rsvp_RX} And prio _RX . Second, RSRP measurement performed according to received SCI format 0-1 is higher than Th (prio _RX ). Third, in time slot->The received SCI format or the same SCI format (if and only if there is a "resource reservation period" field in the received SCI format 0-1) is assumed to be in the slotIs received, determined and->A set of overlapping resource blocks and slots, wherein, q=1, 2, where, Q and j=0, 1, C _resel -1. Here, P' _{rsvp_RX} Is converted into P in logical time slot units _{rsvp_RX} And if P _{rsvp_RX} ＜T _scal And n '-m is less than or equal to P' _{rsvp_RX} Then->Wherein if time slot n belongs to a setThen->Otherwise, time slot->Is belonging to the->A first time slot after time slot n; otherwise q=1. T (T) _scal Is set to be converted into a selection window size T in milliseconds ₂ 。

At 514, the UE determines whether the remaining resources in the selection window are greater than X.M _total 。

If set S _A The number of remaining candidate single-slot resources in the network is less than or equal to X.M _total Then at 516, for each priority value Th (p _i ，p _f ) Th (p) _i ，p _j ) Increasing by 3dB.

If set S _A The number of remaining candidate single-slot resources in the list is greater than X.M _total The UE may report set S to a higher layer at 518 _A And higher layers may randomly select candidate resources for transmission.

General features may be provided for PRS design that may guide how PRS transmissions are designed for SL.

Unlike Uu links that periodically transmit PRSs, transmissions of PRSs over SL may be periodic, semi-persistent, and aperiodic. PRS may be configured by a Location Management Function (LMF) and semi-persistent and aperiodic PRS signals may be triggered by SCI or Medium Access Control (MAC) Control Elements (CEs) carried by a PSSCH. In 3GPP Rel-17, the CSI request is included in the second stage SCI (i.e., SCI format 2-A). Thus, the triggering of semi-persistent and/or aperiodic PRS may also be included in the second stage SCI. SL may require a similar PRS structure.

Similar to Uu positioning, parameters of PRS (such as, for example, resource allocation in time and frequency domains for SL positioning) may be configured/preconfigured by LMF. The UE may expect that it will be configured with SL-PRS IDs, each of which may be defined such that it is associated with multiple sets of SL-PRS resources. The UE may expect that one of these SL-PRS IDs, along with the SL-PRS-ResourceSetID and the SL-PRS-ResourceID, may be used to uniquely identify the DL PRS resource. For periodic PRS transmissions, the UE may need to detect SL-PRS ID information itself. For semi-persistent and aperiodic PRS transmissions, the SL-PRS ID may be included in a SCI (e.g., second stage SCI) or MAC CE.

When the trigger signal for semi-persistent and aperiodic PRS is carried in SCI, the following may exist. If the trigger information is included in the first stage SCI, reserved bits may be used and the number of bits may be preconfigured. If trigger information is included in the second stage SCI, additional bits (1 bit or 2 bits) may be added to the current SCI format 2-a and/or SCI format 2-B.

Thus, the UE may be configured to transmit periodic/semi-persistent/aperiodic PRSs. The UE may be configured by the network with a Tx UE ID (i.e., source ID) associated with the SL-PRS-ID. For semi-persistent/aperiodic PRS transmissions, the SL-PRS-ID may be included in the SCI or MAC CE.

The bandwidth of PRS may also be considered for SL positioning. In general, the accuracy of positioning may be proportional to the bandwidth of the RS used for positioning. In 3GPP Rel-16, the SL resource pool may be composed of SL-NumSubchannel consecutive sub-channels, and the sub-channels may be composed of SL-SubchannelSize consecutive PRBs, where SL-NumSubchannel may be {1, 2..26, 27} and SL-Subchannel Size may be {10,12,15,20,25,50,75,100}. It may be beneficial to have a PRS design that is not based on existing subchannel structures but rather defines PRS signals that can cover the maximum available bandwidth.

Thus, for resource allocation pattern 2 in SL positioning, for high accuracy requirements in timing-based positioning methods, including, for example, time difference of arrival (TDOA) and Round Trip Time (RTT), the allocated PRS and/or CSI-RS resources may cover all of the maximum available bandwidth.

The maximum bandwidth of PRS may also be constrained by the operating frequency band. NR V2X is designed to operate in the operating band in FR1, as defined in table 2.

TABLE 2

As shown, the maximum bandwidth of PRS is 50MHz in band n38 and 70MHz in band n 47. In many cases, more bandwidth is required to improve accuracy. As a first possibility, PRSs may be transmitted in unlicensed spectrum where more bandwidth is available. As a second possibility, carrier aggregation (between multiple licensed carriers, multiple unlicensed carriers, or a combination thereof) may be used.

Thus, the UE may be configured to transmit PRSs on both licensed and unlicensed bands for SL positioning. Transmission of PRS signals with carrier aggregation may be supported for SL positioning.

SL-PRS may be designed by reusing the general principles described above as well as the principles of cellular PRS. In particular, PRS may be defined as a comb. Fig. 8 is a diagram illustrating a slot structure in an RS resource pool according to an embodiment. Reusing this general design, the SL-PRS may be defined with parameters of the start symbol in the slot, the end symbol in the slot, the comb factor (comb-N means one for every N-th RE as shown in FIG. 8), and the offset factor. The offset factor may be defined as a first RE occupied in frequency in a first symbol in which PRS is transmitted.

Fig. 6 is a diagram illustrating a comb index on a first symbol for comb-4 according to an embodiment. Specifically, for comb-4, four combs with indexes 0, 1, 2, 3 are defined.

Some parameters defining the SL-PRS may be implicit. The starting symbol may be the first symbol available (e.g., immediately after the PSCCH). The end symbol may be the last symbol available. The same comb factor can be used for all SL-PRSs.

PRS may be designed as a comb, but other structures may be used as long as a relatively uniform frequency mapping is obtained and system indexing/multiplexing of SL-PRS over one slot may be achieved.

One way to generate SL-PRS is to use CSI-RS. In SL communication, the Tx UE may configure to transmit aperiodic SL CSI reports from the Rx UE over the PSSCH. The UE may transmit CSI-RS only when Channel Quality Indicator (CQI)/Rank Indicator (RI) reporting is enabled through higher layer signaling and the corresponding SCI of the UE triggers SL CQI/RI reporting. CSI-RS in SL may also be used for positioning purposes. Specifically, to apply CSI-RS for SL positioning, a specific configuration is selected. First, in the case of continuous frequency allocation, density=1. Second, code Division Multiplexing (CDM) -type = nocm. Third, from table 3 below, CSI-RS positions within a slot are shown, with only row 1 with comb-4 and row 2 with comb-12 being used.

New signaling may be required to indicate whether the CSI-RS is used for positioning purposes or for legacy purposes. The signaling may be defined by adding a Radio Resource Control (RRC) field (e.g., in the SL CSI-RS configuration).

TABLE 3 Table 3

Table 7.4.1.5.3-1: CSI-RS position within a slot

Thus, CSI-RS in SL may be used for positioning with the following configuration: density=1, cdm-type=nocm, and comb-4 and/or comb-12 in the case of continuous frequency allocation.

For SL-PRS resource allocation, a specific RS resource pool may be used. In the RS resource pool, only RSs may be transmitted. Here, the RS resource pool may include only SL-PRS, but other RSs may be transmitted there as well. The RS resource pool may be configured/preconfigured through RRC signaling and may be defined as a bitmap indicating resources over time and a set of subchannels.

Since SL-PRS preferably occupies the whole bandwidth, the set of subchannels may not be indicated, but rather resources in time. When the RS resource pool occupies the entire carrier, the RS resource pool may be regarded as a special subframe.

Fig. 7 is a diagram illustrating an RS resource pool when the entire carrier bandwidth is used according to an embodiment. Specifically, the RS resource pool includes three positioning slots 702 in a regular slot 704.

When carrier aggregation is used, the RS resource pool slots may be aligned in order for the SL-PRS to occupy all available bandwidth. Thus, when configuring the RS resource pool, the configuration may include a list of carriers occupied by the RS resource pool.

Fig. 8 is a diagram illustrating a slot structure in an RS resource pool according to an embodiment.

At a high level, the slot structure may be similar to a regular slot. The first symbol 802 is used for AGC settings. Subsequent symbols 804 are used for PSCCH transmission (which may overlap with the PSSCH). PRSs may be transmitted in the same region 806 as the PSSCH. The last symbol 808 is a guard time symbol.

The difference between this slot structure and the conventional slot structure is that in the symbols following the PSCCH, the symbols are used for SL-PRS transmissions rather than for the PSSCH. The resource allocation for the SL-PRS may be different from the resource allocation for the PSSCH. For example, there is no subchannel allocation. However, alternative embodiments may allocate subchannels to further multiplex the SL-PRS over frequency. As described herein, SL-PRS resources may be indicated by a comb factor, a start symbol (optional), and an end symbol (optional).

Because the SL-PRS is allocated differently than the PSSCH, a new mapping between the PSCCH and the SL-PRS may be required and a new PSCCH format may be required.

Fig. 9 is a diagram illustrating a slot structure with PSCCH according to an embodiment. The first symbol 902 is used for AGC settings. Subsequent symbols 904 are used for PSCCH transmission. PRSs may be transmitted in the same region 906 as the PSSCH. The last symbol 908 is a guard time symbol.

The PSCCH symbol 904 is divided into N resources. Each resource i corresponds to a SL-PRS resource. The PSCCH resources may be subchannels, PRB sets, or combs.

For example, assuming that the SL-PRS occupies all available time symbols and comb-4 is used, the PSCCH resources may be sub-channels occupying the PSCCH symbols. Thus, four PSCCH resources will be defined.

In some cases, the SL-PRS may be composed of several resources (e.g., a comb-2 resource may be created by aggregating two comb-4 resources). In this case, only a single PSCCH resource may be used, and as an example, a single PSCCH resource would be the PSCCH resource for the lowest resource index.

The message sent on the PSCCH resource occupies the SCI. The SCI may be in a different format and possibly a different size than the existing first stage SCI. Alternatively, the fields may be remapped. Without loss of generality, a new SCI is described, namely SCI format 1-RS. As described above, the SCI may include information such as, for example, sender UE ID, number of reserved resources, period of reserved resources, and/or resource allocation field. This field may be optional if the UE can only be allocated a single SL-PRS resource, since there is a one-to-one correspondence between PSCCH resources and SL-PRS resources. The SCI may also include information such as, for example, SL-PRS ID, SL-PRS resource set ID, and/or SL-PRS resource ID.

The second stage SCI may also be used. In this case, the second stage SCI will be sent on the symbol immediately following the PSCCH. Although referred to as a PSCCH, another channel may be defined to allocate SL-PRS (e.g., RS-PSCCH).

Another alternative for transmitting the SL-PRS over the entire bandwidth is to include in the SCI an indication that the SL-PRS is present in that or future slots. The indication may be carried in the first stage SCI or the second stage SCI. In addition, the SCI may also include a SL-PRS index that specifies the starting sub-carrier of the SL-PRS within the sub-channel. In particular, a SL-PRS with a comb factor of 4 will allow multiplexing (i.e., interleaving) of SL-PRS signals from four different UEs, whereby each UE uses the RE indicated by its comb index to send the SL-PRS within the symbol used to carry the SL-PRS transmission. In addition, the UE may not be allowed to use the remaining REs within the symbol for any other purpose (e.g., data transmission). In this case, if four UEs share a bandwidth and each resource pool configures comb 4, the UEs may be able to spread their SL-PRS transmissions over the entire bandwidth to improve positioning accuracy without interfering with each other.

Fig. 10 is a diagram illustrating SL-PRS locations with two UEs according to an embodiment. The configuration of fig. 10 includes an AGC symbol 1002, a PSCCH symbol 1004, a PSSCH symbol 1006, and a gap 1008.

In fig. 10, two UEs are transmitting SL-PRSs. In the SL-PRS symbol 1014, a first UE uses a first SL-PRS 1010 and a second UE uses a second SL-PRS 1012. Based on the resource pool configuration, there are only two sub-channels, and sl_prs transmission may be configured to be enabled with comb 2. In this case, each of the two UEs has indicated a particular SL-PRS index in the PSCCH (e.g., UE 1 indicates index 1 and UE 2 indicates index 2). Each UE transmits its SL-PRS over the entire frequency band and is not limited to the sub-channel it is transmitting its data. In this example, each UE transmits its SL-PRS on the full frequency band (i.e., first subchannel 1016 and second subchannel 1018).

Fig. 11 is a diagram illustrating SL-PRS locations with a single UE according to an embodiment. The configuration of fig. 11 includes AGC symbol 1102, PSCCH symbol 1104, PSSCH symbol 1106, and gap 1108. The SL-PRS symbols 1114 include SL-PRS resources 1110 and PSSCH resources 1112 on a first subchannel 1116 and a second subchannel 1118.

Specifically, in fig. 11, there is only a single UE, and the UE does not utilize its unreserved REs for SL-PRS, but rather fills the resources corresponding to its SL-PRS index indicated in the PSCCH.

If a UE shares bandwidth with a UE that does not transmit SL-PRS, then the latter UE may have to not use the symbol or at least puncture REs already reserved for SL-PRS transmissions by neighboring UEs sharing the same slot. The reservation may be known from SCI sent by the neighboring UE, where the SCI contains an indication of the presence of PRS in future reservations and SL-PRS index. The behavior of dropping symbols or REs for SL-PRS may be configured for each resource pool. Early release UEs may not be able to access the resource pool indicating PRS presence.

The SL-PRS may be transmitted only in future reservations so that other neighboring UEs may avoid collisions with the SL-PRS. In addition, the reservation may be far enough to meet processing time requirements.

In the case where the UE excludes future resources based on half duplex constraints (i.e., the hypothetical SCI in 510 of fig. 5), it may also exclude symbols configured by the resource pool to carry SL-PRS. Subsequently, 510 of fig. 5 can also be updated to avoid PRS locations so as not to interfere with PRSs transmitted by neighbors.

Fig. 12 is a flowchart illustrating a method for receiving SL-PRS according to an embodiment.

At 1202, the UE may obtain an RS pool configuration. This may be configured/preconfigured by RRC signaling. The RS resource pool configuration is described in detail above. The RRC message indicates, for example, the location of the RS resource pool, what can be sent in it, etc.

At 1204, the UE may receive a slot. The UE attempts to receive the slot on the SL. The UE may first decode the PSCCH.

At 1206, the UE may determine whether the slot is in the RS resource pool. Based on this determination, a different PSCCH format is used.

For example, if the RS resource pool does not occupy all carriers, a portion of the carriers may be used for another resource pool for PSSCH transmission. In this case, the UE may have to monitor two different PSCCH formats at two different frequency locations. Alternatively, some priority rules may be defined (e.g., the UE may attempt to obtain only SL-PRS and not expect to receive the PSSCH in another resource pool).

If the slot is not in the RS resource pool, then a 3gpp rel-17PSCCH monitoring procedure may be used at 1208. In this case, the UE may assume a 3GPP Rel-16/Rel-17PDSCH allocation in terms of subchannels and use an associated PSCCH mapping. The UE may also assume that SCI format 1A is used and that there is a second stage SCI.

If the slot is in the RS resource pool, at 1210, an RS pool specific PSCCH monitoring procedure may be used. In this case, the UE may assume a slot structure, PSCCH-to-SL-SRS resource mapping, and SCI format as described above.

Fig. 13 is a flowchart illustrating a method for receiving SL-PRS according to an embodiment.

At 1302, the UE may obtain a PSSCH configuration. This operation may be hard coded, pre-configured or configured (e.g., by RRC signaling). In order to obtain the PSCCH, the UE may need to know the number of time symbols, the number of frequency resources, and/or the size of the resources, etc.

At 1304, the ue may select a first PSCCH resource. The UE may check all resources from 0 to N-1 in order (assuming N-1 possible SL-PRS resources). On each resource, the UE may attempt to decode the SCI.

In some cases, there may be a large number of SL-PRS resources, which may impose blind decoding constraints on the UE. This may be addressed, for example, by having the UE monitor only a limited set of PSCCH candidates (e.g., 50) until the UE is achieved, and/or using group scheduling, etc.

At 1306, the UE may attempt to decode the SCI. On each PSCCH resource, the UE may blindly attempt to decode SCI with SCI1-Rx format to determine if an assignment exists.

At 1308, the UE determines whether PRS resources are for the UE. If the UE has decoded the SCI, the UE determines if it is an assignment for the UE.

If PRS resources are used for the UE, the UE may receive PRS according to SCI 1_rx parameters at 1310.

If the PRS resource is not for the UE, the UE may determine whether it is the last PSCCH resource at 1312. If it is the last PSCCH resource, the UE may determine that there is no assignment for the UE in the slot at 1314. If it is not the last PSCCH resource, the UE moves to the next PSCCH resource at 1316 and returns to the attempt at 1306 to decode the SCI.

Fig. 14 is a flowchart illustrating a method for transmitting SL-PRS according to an embodiment.

At 1402, the UE may obtain SL-PRS transmission parameters such as, for example, resource pool information and/or which comb to use. Parameters other than the pool information may be obtained from another UE (e.g., a UE that needs to receive the SL-PRS) through, for example, PC5 RRC. Some parameters may also be preconfigured.

At 1404, the UE can determine when and where to transmit PRSs. The mode 2 resource selection procedure may be repeated over the SL-PRS resource pool. The resource selection window and the sensing window may be different from windows used for sensing on other resource pools. Other determinations may include randomly selecting resources.

At 1406, the UE may determine whether to transmit PRSs on a current slot. If the UE determines not to transmit PRS on the current slot, the UE may move to the next slot at 1408. If the UE determines to transmit PRSs on the current time slot, the UE may transmit information associated with PRSs on corresponding PSCCH resources at 1410 and transmit PRSs at 1412.

Once the UE has acquired the resources for transmitting the SL-PRS, it transmits the PSCCH according to the format for the RS pool and the corresponding SL-PRS.

When the RS pool is sparse, re-use of the pattern 2 procedure can be problematic because it increases latency. However, once the resource is selected, the UE can indicate in the conventional SCI (if it has a transmission) that it will send PRS in the next RS pool. The indication may be similar to a CSI-RS indication. The signaling will be slightly different because it needs to indicate that the UE will transmit in future slots in the RS pool (as opposed to CSI-RS transmitted in the slot where the SCI is received). The indication may be in the first stage SCI or the second stage SCI.

This may require the UE to send SCI. Until 3GPP Rel-16, SCI must be associated with PSSCH. However, if independent SCI transmission is supported in the future, then independent SCI (i.e., no associated PSSCH) may be used. In addition, the UE may send PRS reservations only if it has needed to send SCI. If not, PRS reservations are not sent. Further, if the UE does not have data to transmit, the UE may transmit virtual data. Furthermore, considering that PRS transmissions typically occur over several time slots, the UE may send SCI only before sending the first PRS transmission or when resource reselection for PRS has occurred.

As described above, the UE may acquire resources for transmitting PRSs by using a mode 2 resource selection procedure on a regular or special resource pool. The UE may also acquire resources to be transmitted by randomly selecting a set of resources for transmission in a regular or special resource pool.

However, to achieve a relatively good positioning estimate, the UE may transmit its PRS over the entire bandwidth with minimal interference. This may be done in one slot or by using a comb structure to allow two or more UEs to share bandwidth and transmit their PRS signals simultaneously. In either case, the transmission of PRS signals may potentially interfere with the transmission of other UEs (if the puncturing approach discussed above is not considered). In addition, a UE that is transmitting PRS may attempt to acquire a large bandwidth, which may not be possible or may cause significant delay in discovering opportunities, such that the full bandwidth, or at least a majority thereof, is empty. To address this issue, the priority level of SL PRS may be adjusted to a high level and may be associated with a new set of RSRP thresholds. In particular, two sets of RSRP thresholds may be configured, whereby the first set is for regular transmissions and the second set is for PRS transmissions.

This allows UEs that are transmitting PRSs to transmit with less delay by allowing them to preempt transmissions of regular UEs and protecting them from preemption by neighboring UEs.

In addition, this reduces the chance of collision with regular UE transmissions, as the newly assigned RSRP threshold may be set to a lower value and thus prevent other UEs from accessing the resources reserved for PRS transmissions.

When signaling the presence of PRSs to a neighboring UE, a new high priority level may be assigned, which may be carried in the first stage SCI to indicate the presence of PRSs. Alternatively, to ensure backward compatibility, PRS may always be sent using the highest priority (i.e., priority 0), although there is still an opportunity to collide with ultra-reliable low latency communication (URLLC) traffic;

the signaling may also be performed by adding an additional field in the first stage SCI or the second stage SCI or the new second stage SCI format to indicate the presence of PRS, wherein the additional field may be used to enhance the priority field when indicating the highest possible priority.

Thus, when the UE determines a subset of resources to report to a higher layer in SL-PRS resource selection in SL resource allocation pattern 2, transmissions of the UE selecting resources for SL-PRS may have a higher priority than other signals/channels for SL communication. This may be achieved by using the highest priority for backward compatibility or by adding a new exclusive priority level for PRS. In addition, the UE may be configured with different RSRP thresholds for priority combinations of SL-PRS resource allocation (i.e., introducing a new IE SL-Thres-PRS-RSRP-List for SL positioning).

In order for the UE to know when to transmit the SL-PRS, the UE may transmit the SL-PRS as needed. When a UE needs to perform positioning, it may send a request to other UEs to send SL-PRS. However, the UE may also autonomously transmit SL-PRS without being probed. In this case, the UE may determine when to transmit the SL-PRS based on a pre-configuration or a random determination.

Regarding pre-configuration, a UE may be pre-configured to transmit on some timeslots based on, for example, its UE ID.

Regarding the random determination, the UE may randomly transmit on a given RS slot based on a given probability.

The SL-PRS transmission rate may be determined based on, for example, a Code Block Group (CBG) (or equivalent measurement).

In such a procedure, the UE may indicate its location in the PSCCH associated with the SL-PRS. The receiving UE may then decode the PSCCH, obtain the Tx UE position, and obtain a corresponding SL Reference Signal Time Difference (RSTD) using the associated SL-PRS.

For PRS resource allocation pattern 1, the gnb manages SL resources. PRS resource allocation for Uu link positioning may be reused with some modifications. The number of available symbols for data and reference signals in SL is 12 for the case without feedback and 9 for the case with feedback. PRS resource allocation in SL requires the following changes. The first symbol of DL PRS within a slot is greater than or equal to 1. For the case without feedback, the size of the SL-PRS resources in the time domain may be {2,4,6, 12} and the comb size may be {2,4,6, 12}. For the case with feedback, the size of the SL-PRS resources in the time domain may be {2,4,6} and the comb size may be {2,4,6}.

The SL-PRS configuration may be configured by RRC signaling. The indication of the UE to send the SL-PRS may be done by RRC signaling, a new MAC CE, or a new DL Control Information (DCI) format (DCI Format 5-B). The new DCI format indicates when and where to transmit the SL-PRS.

When the SL-PRS is not transmitted in the RS resource pool, it shares the pool with the PSSCH and possibly other SL-PRSs. In this case, the SL resource procedure may be reused mainly in case of some changes. First, SL-PRS occupies only some REs, not the entire slot. Second, other unoccupied REs may be used for PSSCH transmission. SL-PRS needs to occupy the entire carrier.

For SL-PRS only some REs are occupied, when reservation is indicated, the UE needs to signal that it is only used for SL-PRS and only a limited set of REs are used within the sub-channel. This can be accomplished by reusing the existing SCI format 1-a with the following changes. First, one bit (taken from the reserved bit) indicates that the reservation is for SL-PRS. Second, as described above, the existing frequency resource allocation field is interpreted as signaling SL-PRS.

The mode-2 SL resource allocation procedure may be slightly modified for other unoccupied REs for PSSCH transmission. A step may be added to the 3GPP Rel-16SL resource allocation procedure for mode-2 shown in fig. 5, which may ensure that PRS resources occupy the maximum available bandwidth.

Fig. 15 is a flowchart illustrating a method for resource selection for mode-2 in SL positioning according to an embodiment.

At 1502, a selection window may be set as described above with respect to 502 of FIG. 5.

At 1504, a sensing window may be set, as described above with respect to 504 of fig. 5, and the time slot may be monitored by decoding the PSCCH and measuring RSRP.

At 1506, a threshold may be set according to the priority value as described above with respect to 506 of fig. 5.

At 1508, initial set S, as described above with respect to 508 of FIG. 5 _A May be initialized to include all candidate single slot resources.

At 1510, the UE may exclude resources if restricted, as described above with respect to 510 of fig. 5.

At 1512, as described above with respect to 512 of fig. 5, if resources are occupied by UEs with higher priority and RSRP > Th, the UE may exclude those resources.

At 1520, the UE determines whether the remaining resources can cover all PRBs on frequency. If the remaining resources cannot cover all PRBs in the frequency, then at 1522, a priority value Th (p _i ，p _j ) Th (p) _i ，p _j ) The increase is 3dB.

If the remaining resources can cover all PRBs on the frequency, then at 1514, the UE determines whether the remaining resources in the selection window are greater than X.M, as described above with respect to 514 of FIG. 5 _total 。

If set S _A Remaining candidate single slot resources in (a)The number is less than or equal to X.M _total Then at 1516, for each priority value Th (p _i ，p _j ) Th (p) _i ，p _j ) The increase is 3dB.

If set S _A The number of remaining candidate single-slot resources in the list is greater than X.M _total Then at 1518 the UE may combine set S as described above with respect to 518 of fig. 5 _A The remaining resources of (a) are reported to higher layers and the higher layers may randomly select candidate resources for transmission.

Thus, for SL PRS resource allocation in mode-2, the set of candidate resources reported by the UE should cover the entire available bandwidth (i.e., all subchannels) for SL positioning.

For SL positioning in FR2, beam scanning may be required during measurement of PRS. Thus, at least 2 DL PRS resource sets and/or CSI-RS resource sets may be provided for each UE. This achieves two-phase beam scanning by allowing one set of PRS/CSI-RS resources to be a narrow beam and one set of PRS/CSI-RS resources to be a wide beam. Furthermore, the association information between PRS/CSI-RS resources is within two sections (e.g., PRS/CSI-RS resources X and Y from set #2 are nested in PRS/CSI-RS resource Z from set # 1). PRS/CSI-RS resources belonging to the same set of resources may have the same time-frequency domain configuration. A new QCL relationship between PRS/CSI-RS resources in two different sets of PRS/CSI-RS resources may be introduced. If one PRS/CSI-RS resource in the first set of resources is a QCL source of multiple PRS/CSI-RS resources in the second set of resources, the first set of PRS/CSI-RS resources is configured for a wide beam and the second set of resources is configured for a narrow beam.

Thus, there may be at least two sets of PRS/CSI-RS resources for SL positioning. A new QCL relationship may be introduced in which the UE measures QCL source PRS/CSI-RS resources in one set of PRS/CSI-RS resources for a broad beam and all corresponding PRS/CSI-RS resources to the source PRS/CSI-RS resource QCL in another set of PRS/CSI-RS resources for a narrow beam.

For beamforming in FR2, the beam may be directionally formed at the transmitter and the receiver. PRS/CSI-RS resources occupied by other sender UEs may also be utilized without collision if the directions of the transmit/receive beams are different. For Uu link positioning, the Tx beam direction (or PRS resource ID) may be included in a common NR positioning IE in the LTE Positioning Protocol (LPP) from LMF to UE. For SL positioning, the Tx beam direction (or PRS/CSI-RS resource ID) may be included in the SCI.

Thus, for SL positioning in FR2, PRS resource IDs associated with spatial transmission filters at Tx UEs may be included in SCIs (i.e., first stage SCI or second stage SCI).

When transmitting on the SL, the variation in received signal power at the UE in the SL may be more pronounced than on the Uu link. This difference may be due to the fact that the UE may receive signals from very close or very far UEs. This makes AGC difficult to perform. AGC is a process performed by a receiver to automatically adjust the amplifier gain so that the Radio Frequency (RF) signal matches the dynamic range of an analog-to-digital converter (ADC).

For SL communication, the UE may transmit at the same power during one slot. The first symbol of the slot may be a repetition of the second symbol. The Rx UE may use the symbol to establish its AGC.

AGC setting may be more difficult if a dedicated resource pool is used for SL-PRS. Specifically, on the first symbol(s), the UE receives the first stage SCI and for the remainder of the slot, the UE receives the SL-PRS. Thus, the received power on the first symbol may be different from the received power on the other slots.

Fig. 16 is a diagram illustrating an AGC design for slots of a SL-PRS according to an embodiment. After the SCI symbol 1604, the AGC symbol 1602 is replicated at the first symbol 1606 where transmission of the SL-PRS 1608 occurred to reset the AGC. The guard time symbol 1610 immediately follows the SL-PRS 1608. However, this solution is not optimal because it may result in additional symbol overhead (i.e., 7% overhead per slot). Accordingly, it may be desirable to provide a slot structure that enables AGC settings for SL-PRS transmissions without adding additional symbols for the AGC settings.

SL-PRS may occur in separate dedicated resource pools. However, if a link has been established, for example, between two UEs, or in order to reduce positioning delay, it may be desirable to send SL-PRS with the data.

When transmitting the SL-PRS with data, the UE may need to indicate whether the SL-PRS is present or absent. Thus, signaling for indicating whether the SL-PRS is transmitted with data is required.

To achieve SL positioning with high accuracy, NR UEs may be able to transmit PRSs over a large bandwidth. To achieve this, one may rely on a special resource pool, where only PRS signals are transmitted without any data. Specifically, in this resource pool, there is only control signaling (i.e., PSCCH) and PRS. The PSCCH provides reserved resources on which PRS signals may be transmitted and provides the source ID of the NR UE that is transmitting the reference signal.

Fig. 17 is a diagram illustrating AGC in a slot structure according to an embodiment. The first symbol 1702 for AGC precedes the PSCCH symbol 1704. The region 1708 for transmitting SL-PRS is a wideband signal spanning the entire bandwidth, and PSCCH symbols 1704 may be limited to one subchannel. A guard time symbol 1710 immediately follows region 1708. Thus, the power on symbols containing the PSCCH is different from the power on symbols containing only SL-PRS. When multiple SL-PRS signals from multiple UEs are multiplexed in a resource pool with their associated PSCCHs, this may be amplified to achieve better utilization of the available spectrum.

Without careful design, a UE transmitting its PSCCH at subchannel X may be required to achieve AGC training for the full bandwidth of its PRS signal despite the fact that its PSCCH and its associated AGC symbols at the beginning of a slot span only one subchannel. This would result in additional overhead.

One way to implement AGC training of SL-PRS is to reserve one symbol before the SL-PRS symbols for AGC training. The AGC symbol is a repetition of a first SL-PRS symbol, where the first SL-PRS symbol is the actual starting symbol for useful information. This design of AGC is shown in fig. 16. However, this design has a large overhead because it introduces two symbols for AGC training in one slot (one for PSCCH and the other for SL-PRS). To solve this problem, two options are proposed to implement AGC training for SL-PRS.

As a first option for implementing AGC training of SL-PRS, if SL-PRS resource allocation is performed for only a single UE in a slot, only one symbol at the beginning of the slot is used for AGC training. The symbol is a repetition of the second symbol of the slot.

Fig. 18A is a diagram illustrating a slot structure with PSCCH repetition according to an embodiment. The first symbol 1802 for AGC precedes the PSCCH symbol 1804. The region 1808 for transmitting SL-PRS is a wideband signal spanning the entire bandwidth, while PSCCH symbols 1804 may be limited to one subchannel. The guard time symbol 1810 immediately follows the region 1808. Assuming that PSCCH 1804 occupies only a small bandwidth (i.e., one subchannel), the remaining frequency resources within the same symbol occupied by PSCCH 1804 are filled by repetitions of PSCCH transmission 1812.

Fig. 18B is a diagram illustrating a slot structure with SL-PRS repetition according to an embodiment. Considering that PSCCH 1804 occupies only a small bandwidth (i.e., one subchannel), the remaining frequency resources within the same symbol occupied by PSCCH 1804 are filled by repetition of SL-PRS resources 1814.

The embodiment of fig. 18A may enhance the reliability of the PSCCH channel because the transmissions may be jointly decoded. The number of repetitions of the PSCCH may be selected to match the frequency occupation of the corresponding SL-PRS. For example, if the comb-4 factor is used for SL-PRS, where every fourth occupies a single RE, the repetition of PSCCH must be such that every fourth occupies one RE on a PSCCH symbol (i.e., the number of REs occupied by PSCCH matches the number of REs occupied by SL-PRS). When the SL-PRS occupies M REs and the plurality of PSCCHs occupy N REs (where M > N), repetition of the resources of the PSCCHs may be performed as follows.

The entire resource of multiple PSCCHs may be repeated in the frequency domainAnd twice. Front in multiple PSCCH resource areasThe REs may be duplicated and placed in empty resource locations in the frequency domain.

The solution can be extended to the case where there are multiple PSCCHs/UEs in the same subframe. The same frequency occupation can be more easily achieved if the PSCCHs are interleaved, as described in more detail below. If the PSCCHs are not interleaved, they must be repeated in such a way that they do not interfere with each other.

Fig. 19 is a diagram illustrating a slot structure of a SL-PRS with multiple PSCCH repetitions according to an embodiment. The first symbol 1902 for AGC precedes the PSCCH symbol 1904. The region 1908 for transmitting SL-PRS is a wideband signal that spans the entire bandwidth. The guard time symbol 1910 immediately follows the region 1908. The plurality of PSCCHs (# 0- # 3) may be repeated in a Frequency Division Multiplexed (FDM) manner.

According to the power control mechanism, the UE may determine the power P of the PSCCH transmission on the resource pool in PSCCH and SL-PRS transmission occasion i _PSCCH (i) As shown in the following equation (5):

wherein P is _SL-PRS (i) Is the power used for SL-PRS transmission,is the number of resource elements for PSCCH transmission in PSCCH and SL-PRS transmission occasion i, +.>Is the number of resource elements for PSCCH and SL-PRS transmission occasion i.

As an example of power adjustment for PSCCH and SL-PRS transmissions, N REs (e.g., n=4 in fig. 19) are occupied on PSCCH 1902, where 2N is the number of REs occupied by SL-PRS 1908. The UE transmits the PSCCH at 3dB lower power than the SL-PRS transmission. A map can be derived that identifies where the repetitions are located. In general, when the SL-PRS occupies M REs and the multiple PSCCHs occupy N REs (where M > N), repetition of the resources of the multiple PSCCHs may be performed as follows.

The entire resource of multiple PSCCHs may be repeated in the frequency domainAnd twice. Front in multiple PSCCH resource areasThe REs may be duplicated and placed at null resource locations 1906 in the frequency domain.

As a second option for implementing AGC training for SL-PRS, in case of UE multiplexing, one symbol at the beginning of a slot may be used for AGC training and the symbol may be a repetition of the second symbol of the slot (i.e. a repetition of the first symbol carrying PSCCH). The PSCCHs may also be interleaved such that the bandwidth occupied by the PSCCHs matches the bandwidth of the SL-PRS, given that the intended PRS signals are staggered in time and have a special pattern in the frequency domain that covers the entire bandwidth. In particular, the AGC training for SL-PRS may be implemented considering an interleaved PSCCH pattern.

Fig. 20 is a diagram illustrating a slot structure of SL-PRS with PSCCH interleaving according to an embodiment. The first resources 2002 for transmitting PSCCH and SL-PRS for a first UE and the second resources 2004 for transmitting PSCCH and SL-PRS for a second UE 2004 may be interleaved with each other in the frequency domain across AGC symbols 2006, PSCCH symbols 2008 and SL-PRS portions 2010 on a first subchannel 2014 and a second subchannel 2016. The guard time symbol 2012 immediately follows the SL-PRS portion 2010.

While this approach has advantages, in some cases the PSCCH may occupy a much smaller bandwidth than the SL-PRS. In this case, AGC training may not be performed for all subcarriers to be occupied by SL-PRS. To address this problem, PSCCH repetition may be used over an interlace design to match the number of subcarriers occupied by the SL-PRS signal and the corresponding PSCCH.

Fig. 21 is a diagram illustrating a slot structure of SL-PRS with PSCCH interleaving and repetition according to an embodiment. The first resources 2102 for transmitting PSCCH and SL-PRS for a first UE and the second resources 2104 for transmitting PSCCH and SL-PRS for a second UE may be interleaved with each other in the frequency domain across AGC symbols 2106, PSCCH symbols 2108, and SL-PRS portions 2110 on first subchannels 2114 and second subchannels 2116. The guard time symbol 2112 immediately follows the SL-PRS portion 2110.

The PSCCH is repeated to match the bandwidth of the SL-PRS. The repeated portions of the interleaved PSCCHs may not necessarily cover a complete PSCCH. For example, if the SL-PRS has 25 REs and the PSCCH has 10 REs, the PSCCH will be repeated 2.5 times to achieve the necessary AGC training. In this case, the remaining 0.5 repetitions of PSCCH are not necessarily possible. However, in practice, the interleaving structure of the PSCCH and SL-PRS patterns may be preconfigured such that the SL-PRS REs are integer multiples of the PSCCH REs.

PSCCH interleaving for AGC designs is advantageous because transmissions from multiple Tx UEs can be multiplexed in the same time slot. Since PSCCH transmission occurs on the same sub-carriers used to transmit the PSCCH, additional symbols need not be dedicated to AGC training at the beginning of the SL-PRS. There is a 1-1 mapping between PSCCH interlace index and corresponding SL-PRS pattern.

In another approach, rather than repeating the interleaved PSCCH, the ratio between PSCCH and SL-PRS REs may be basedThe transmission power of the PSCCH is adjusted to maintain the same energy per symbol. In this case, the AGC can still be trained without repeating the PSCCH. The interleaving of PSCCH and SL-PRS will be different. For example, if the ratio is->The PSCCH may have a comb 8 structure while the SL-PRS has a comb 4 structure.

In another SL-PRS resource pool configuration, SCI (i.e., PSCCH) and SL-PRS may not be in the same slot. In this case, AGC training is still required. One method is captured in fig. 21, where one symbol before the SL-PRS symbol is used for AGC training and one symbol after the SL-PRS symbol is used for Tx/Rx switching in the slot. The SCI may schedule the resources for the SL-PRS in one slot and in different slots (the SCI may also be transmitted in different sub-channels or even in different carriers in case of carrier aggregation).

Fig. 22 is a diagram illustrating a slot structure without SCI according to an embodiment. The first symbol 2202 for AGC precedes the region 2208 for SL-PRS transmission. The guard time symbol 2210 immediately follows the region 2208. In this case, the resource allocation 2208 for SL-PRS may be configured by assistance data for SL positioning. When the UE is in mode-1, it may be configured with SL-PRS IDs, each defined such that it may be associated with multiple SL-PRS resource sets. The UE may expect that one of these SL-PRS IDs, together with the SL-PRS-ResourceEid and the SL-PRS-ResourceID, may be used to uniquely identify the SL PRS resource. When the UE is in mode-2, it may reuse the previous configuration or default configuration of the SL-PRS ID of the UE. To avoid collisions between multiple UEs on the SL-PRS transmission, there is a 1 between the SL-PRS ID and each UE within a certain distance range: 1 mapping. For example, within a geographic region, each UE is configured to be associated with a unique SL-PRS ID, and there is no collision even when multiple UEs transmit SL-PRSs simultaneously.

In multiplexing the SL-PRS with data, the PSCCH symbol is divided into N resources. Each resource i corresponds to a SL-PRS resource. The PSCCH resources may be subchannels, PRB sets, or interlace indexes.

For example, SL-PRS may occupy all available time symbols and comb-4 may be used. The PSCCH resource may be a subchannel that occupies PSCCH symbols with 4 interlace indexes, allowing multiplexing of 4 PSCCH transmissions in the same slot.

Although the SL-PRS may be transmitted in a dedicated resource pool to reduce complexity, in some cases it may be preferable to jointly transmit data and the SL-PRS to achieve better resource utilization.

An alternative for transmitting the SL-PRS across the full bandwidth is to include in the SCI an indication that there is an SL-PRS in the slot or future slot (i.e., future reservation) and then transmit the SL-PRS in REs configured to carry RSs within the slot and sub-channel indicated by the SCI. An indication of the presence of the SL-PRS in the slot or in a later reserved slot may be carried in the first stage SCI or the second stage SCI. The indication may be carried in a dedicated field for the SL-PRS (e.g., one bit is added to indicate the presence of the SL-PRS in the current or future time slot), or it may share the same field of the SL CSI request based on a pre-configuration. Specifically, the RRC configuration may be used to indicate whether the CSI-RS or SL-PRS is to be indicated by a CSI-RS 1-bit field (i.e., a "CSI request" 1-bit field) currently present in the second stage SCI in 3GPP Rel-16. The configuration may also be made such that only CSI-RS may be triggered in some slots (e.g., odd slots) and SL-PRS may be indicated by CSI-RS 1 bit field in the second stage SCI in other slots (e.g., even slots). The RRC configuration may be performed per resource pool or per UE. In addition, the configuration may be performed such that both CSI-RS and SL-PRS may be triggered by the same bit field. In this case, the Rx UE may rely on other conditions when deciding whether to treat this field as an indication of CSI request or the presence of SL-PRS. For example, if the Rx UE sends a request for PRS, it may be assumed that the upcoming CSI field will be used for SL-PRS indication. The indication of the SL-PRS request may be carried, for example, in the first stage SCI or the second stage SCI and implicitly (i.e., by setting one or more fields to a predefined value) or explicitly (i.e., by adding a new field). These requests may only be allowed if the resource pool is configured to allow SL-PRS transmissions.

In addition, the resource pool may be configured to allow multiple SL-PRS indexes, and the SL-PRS may be allowed to span the entire bandwidth through the resource pool configuration in a particular slot. These configured SL-PRS indexes are important in cases where the SL-PRS is wideband and can span beyond the sub-channels reserved for SCI. In particular, the resource pool may be configured by any of the following methods.

In a first approach, the SL-PRS may be present only within the sub-channel indicated by the Frequency Resource Indication Value (FRIV) field in the SCI. In this case, only the presence of SL-PRS need be indicated, and no SL-PRS index is needed. SL-PRS may be very similar to CSI-RS in the sense that they occupy the same resources.

In the second approach, the SL-PRS is wideband and may exist over the entire bandwidth in a particular slot. In this case, an indication that there is a SL-PRS is required, and also an SL-PRS index is required so that the SL-PRSs of a plurality of UEs can be multiplexed. For example, one UE may indicate SL-PRS index 1 and a second UE may indicate SL-PRS index 2.

The SCI (i.e., the first stage SCI or the second stage SCI) may also include a SL-PRS index and a SL-PRS presence indication (which may also be performed implicitly by setting one or more fields to a predefined value). For example, setting a Time Resource Indication Value (TRIV) field to a particular value may be used to indicate the presence of SL-PRS and the selected SL-PRS index. Such reuse of the SCI field may also be limited to a resource pool (or slot). The SL-PRS is configured when the SL-PRS is indicated as present.

Fig. 23 is a flow chart illustrating reception of SL-PRS multiplexed with data according to an embodiment. At 2302, the UE may receive the SCI with the CSI request. At 2304, the UE may evaluate the condition. At 2306, the UE may determine whether the condition indicates a SL-CSI-RS. If the condition indicates SL-CSI-RS, then at 2308 the UE may receive PSSCH and SL-SCI-RS according to the 3GPP Rel-16 procedure.

If the condition does not indicate a SL-CSI-RS, then the UE may determine that a SL-PRS is present at 2310. At 2312, the UE may perform measurements on the SL-PRS, and at 2314, the UE may process the PDSCH assuming that the PDSCH is rate matched around the SL-CSI-RS.

In addition, the SL-PRS may be configured by PC5 RRC and detailed IEs are listed as follows.

Referring to fig. 24, an electronic device 2401 in a network environment 2400 can communicate with an electronic device 2402 via a first network 2498 (e.g., a short-range wireless communication network) or with an electronic device 2404 or server 2408 via a second network 2499 (e.g., a long-range wireless communication network). The electronic device 2401 may communicate with the electronic device 2404 via a server 2408. The electronic device 2401 may be implemented as the sender UE or the receiver UE described above, and communicates with an electronic device 2404 or a server 2408, which may be implemented as a gNB or a corresponding UE.

The electronic device 2401 may include a processor 2420, a memory 2430, an input device 2440, a sound output device 2455, a display device 2460, an audio module 2470, a sensor module 2476, an interface 2477, a haptic module 2479, a camera module 2480, a power management module 2488, a battery 2489, a communication module 2490, a Subscriber Identity Module (SIM) card 2496, or an antenna module 2494. In one embodiment, at least one of the components (e.g., the display device 2460 or the camera module 2480) may be omitted from the electronic device 2401, or one or more other components may be added to the electronic device 2401. Some components may be implemented as a single Integrated Circuit (IC). For example, a sensor module 2476 (e.g., a fingerprint sensor, iris sensor, or illuminance sensor) may be embedded in a display device 2460 (e.g., a display).

The processor 2420 may execute software (e.g., the program 2440) to control at least one other component (e.g., hardware or software component) of the electronic device 2401 coupled to the processor 2420, and may perform various data processing or calculations.

As at least part of the data processing or calculation, the processor 2420 may load commands or data received from another component (e.g., the sensor module 2446 or the communication module 2490) into the volatile memory 2432, process commands or data stored in the volatile memory 2432, and store the resulting data in the non-volatile memory 2434. The processors 2420 may include a main processor 2421 (e.g., a Central Processing Unit (CPU) or an Application Processor (AP)) and an auxiliary processor 2423 (e.g., a Graphics Processing Unit (GPU), an Image Signal Processor (ISP), a sensor hub processor, or a Communication Processor (CP)) that may operate independently of or in conjunction with the main processor 2421. Additionally or alternatively, the secondary processor 2423 may be adapted to consume less power than the primary processor 2421, or to perform certain functions. The secondary processor 2423 may be implemented separately from or as part of the primary processor 2421.

The secondary processor 2423 may control at least some of the functions or states associated with at least one of the components of the electronic device 2401 (e.g., the display device 2460, the sensor module 2476, or the communication module 2490) in place of the primary processor 2421 when the primary processor 2421 is in an inactive (e.g., sleep) state, or with the primary processor 2421 when the primary processor 2421 is in an active state (e.g., executing an application). The secondary processor 2423 (e.g., an image signal processor or a communication processor) may be implemented as part of another component (e.g., a camera module 2480 or a communication module 2490) functionally related to the secondary processor 2423.

The memory 2430 can store various data used by at least one component of the electronic device 2401 (e.g., the processor 2420 or the sensor module 2476). The various data may include, for example, software (e.g., program 2440) and input data or output data for commands associated therewith. The memory 2430 can include volatile memory 2432 or nonvolatile memory 2434.

The program 2440 may be stored as software in the memory 2430 and may include, for example, an Operating System (OS) 2442, middleware 2444, or applications 2446.

The input device 2450 can receive commands or data from outside the electronic device 2401 (e.g., a user) to be used by another component of the electronic device 2401 (e.g., the processor 2420). The input device 2450 can include, for example, a microphone, a mouse, or a keyboard.

The sound output device 2455 can output a sound signal to the outside of the electronic device 2401. The sound output device 2455 can include, for example, a speaker or a receiver. The speaker may be used for general purposes, such as playing multimedia or recording, and the receiver may be used to receive incoming calls. The receiver may be implemented separately from the speaker or as part of the speaker.

The display device 2460 can visually provide information to the outside (e.g., user) of the electronic device 2401. The display 2460 can include, for example, a display, a hologram device, or a projector, and control circuitry for controlling a corresponding one of the display, the hologram device, and the projector. The display device 2460 can include touch circuitry adapted to detect touches, or sensor circuitry (e.g., pressure sensors) adapted to measure the intensity of forces caused by touches.

The audio module 2470 can convert sound into electrical signals and vice versa. The audio module 2470 may obtain sound via the input device 2450 or output sound via the sound output device 2455 or headphones of the external electronic device 2402 that is directly (e.g., wired) or wirelessly coupled to the electronic device 2401.

The sensor module 2476 can detect an operational state (e.g., power or temperature) of the electronic device 2401 or an environmental state (e.g., a state of a user) external to the electronic device 2401 and then generate an electrical signal or data value corresponding to the detected state. The sensor module 2476 can include, for example, a gesture sensor, a gyroscope sensor, an atmospheric pressure sensor, a magnetic sensor, an acceleration sensor, a grip sensor, a proximity sensor, a color sensor, an Infrared (IR) sensor, a biometric sensor, a temperature sensor, a humidity sensor, or an illuminance sensor.

The interface 2477 can support one or more specified protocols for coupling the electronic device 2401 directly (e.g., wired) or wirelessly with the external electronic device 2402. Interface 2477 can include, for example, a High Definition Multimedia Interface (HDMI), a Universal Serial Bus (USB) interface, a Secure Digital (SD) card interface, or an audio interface.

The connection end 2478 can include a connector via which the electronic device 2401 can physically connect with the external electronic device 2402. The connection end 2478 can include, for example, an HDMI connector, a USB connector, an SD card connector, or an audio connector (e.g., a headphone connector).

Haptic module 2479 can convert an electrical signal into a mechanical stimulus (e.g., vibration or movement) or an electrical stimulus that can be recognized by a user via a sense of touch or kinesthetic sense. Haptic module 2479 can include, for example, a motor, a piezoelectric element, or an electrostimulator.

The camera module 2480 may capture still images or moving images. The camera module 2480 can include one or more lenses, image sensors, image signal processors, or flash lamps. The power management module 2488 can manage power provided to the electronic device 2401. The power management module 2488 can be implemented as at least a portion of a Power Management Integrated Circuit (PMIC), for example.

Battery 2489 can provide power to at least one component of electronic device 2401. Battery 2489 can include, for example, a non-rechargeable primary battery, a rechargeable secondary battery, or a fuel cell.

The communication module 2490 may support establishing a direct (e.g., wired) communication channel or a wireless communication channel between the electronic device 2401 and an external electronic device (e.g., electronic device 2402, electronic device 2404, or server 2408) and performing communication via the established communication channel. The communication module 2490 can include one or more communication processors that can operate independently of the processor 2420 (e.g., an AP) and support direct (e.g., wired) or wireless communication. The communication module 2490 can include a wireless communication module 2492 (e.g., a cellular communication module, a short-range wireless communication module, or a Global Navigation Satellite System (GNSS) communication module) or a wired communication module 2494 (e.g., a Local Area Network (LAN) communication module or a Power Line Communication (PLC) module). A respective one of these communication modules may be via a first network 2498 (e.g., a short-range communication network such as Bluetooth ^TM Wireless fidelity (Wi-Fi) direct or infrared data association (IrDA) standard) or a second network 2499 (e.g., a long-range communication network such as a cellular network, the internet, or a computer network (e.g., a LAN or Wide Area Network (WAN)) with an external electronic device. These various types of communication modules may be implemented as a single component (e.g., a single IC), or may be implemented as multiple components (e.g., multiple ICs) separate from one another. The wireless communication module 2492 can identify and authenticate using subscriber information (e.g., international Mobile Subscriber Identity (IMSI)) stored in the subscriber identification module 2496An electronic device 2401 in a communication network, such as a first network 2498 or a second network 2499, is authenticated.

The antenna module 2497 can send signals or power to or receive signals or power from an outside of the electronic device 2401 (e.g., an external electronic device). The antenna module 2497 can include one or more antennas and from among them, at least one antenna suitable for a communication scheme used in a communication network such as the first network 2498 or the second network 2499 can be selected, for example, by the communication module 2490 (e.g., the wireless communication module 2492). Signals or power may then be transmitted or received between the communication module 2490 and the external electronic device via the selected at least one antenna.

Commands or data may be sent or received between the electronic device 2401 and the external electronic device 2404 via a server 2408 coupled to the second network 2499. Each of the electronic devices 2402 and 2404 may be the same type or different type of device than the electronic device 2401. All or some of the operations to be performed at the electronic device 2401 may be performed at one or more of the external electronic devices 2402, 2404, or 2408. For example, if the electronic device 2401 should perform a function or service automatically or in response to a request from a user or another device, the electronic device 2401 may request the one or more external electronic devices to perform at least a portion of the function or service instead of or in addition to performing the function or service. The one or more external electronic devices receiving the request may perform at least a portion of the requested function or service or additional functions or additional services related to the request and communicate the result of the performance to the electronic device 2401. The electronic device 2401 may provide the result as at least a portion of the reply to the request with or without further processing of the result. To this end, for example, cloud computing, distributed computing, or client-server computing techniques may be used.

Embodiments of the subject matter and the operations described in this specification can be implemented in digital electronic circuitry, or in computer software, firmware, or hardware, including the structures disclosed in this specification and their structural equivalents, or in combinations of one or more of them. Embodiments of the subject matter described in this specification can be implemented as one or more computer programs (i.e., one or more modules of computer program instructions) encoded on a computer storage medium for execution by, or to control the operation of, data processing apparatus. Alternatively or additionally, the program instructions may be encoded on a manually generated propagated signal that is generated to encode information for transmission to suitable receiver apparatus for execution by a data processing apparatus, e.g., a machine-generated electrical, optical, or electromagnetic signal. The computer storage medium may be, or be included in, a computer-readable storage device, a computer-readable storage substrate, a random or serial access memory array or device, or a combination thereof. Furthermore, while the computer storage medium is not a propagated signal, the computer storage medium may be a source or destination of computer program instructions encoded in an artificially generated propagated signal. Computer storage media may also be or be included in one or more separate physical components or media (e.g., multiple CDs, disks, or other storage devices). In addition, the operations described in this specification may be implemented as operations performed by a data processing apparatus on data stored on one or more computer readable storage devices or received from other sources.

Although this description may contain many specific implementation details, the implementation details should not be construed as limiting the scope of any claimed subject matter, but rather as descriptions of features specific to particular embodiments. Certain features that are described in this specification in the context of separate embodiments can also be implemented in combination in a single embodiment. Conversely, various features that are described in the context of a single embodiment can also be implemented in multiple embodiments separately or in any suitable subcombination. Furthermore, although features may be described above as acting in certain combinations and even initially claimed as such, one or more features from a claimed combination can in some cases be excised from the combination, and the claimed combination may be directed to a subcombination or variation of a subcombination.

Similarly, although operations are depicted in the drawings in a particular order, this should not be understood as requiring that such operations be performed in the particular order shown or in sequential order, or that all illustrated operations be performed, to achieve desirable results. In some cases, multitasking and parallel processing may be advantageous. Moreover, the separation of various system components in the embodiments described above should not be understood as requiring such separation in all embodiments, and it should be understood that the described program components and systems can generally be integrated together in a single software product or packaged into multiple software products.

Thus, particular embodiments of the subject matter have been described herein. Other embodiments are within the scope of the following claims. In some cases, the actions recited in the claims can be performed in a different order and still achieve desirable results. In addition, the processes depicted in the accompanying drawings do not necessarily require the particular order shown, or sequential order, to achieve desirable results. In some embodiments, multitasking and parallel processing may be advantageous.

As will be recognized by those skilled in the art, the innovative concepts described herein can be modified and varied over a wide range of applications. Accordingly, the scope of the claimed subject matter should not be limited to any of the specific exemplary teachings discussed above, but is instead defined by the appended claims.

Claims

1. A method for Side Link (SL) positioning, comprising:

determining, by a User Equipment (UE), a resource pool for receiving SL Positioning Reference Signals (PRS);

receiving a time slot at the UE;

determining, by the UE, whether the slot includes resources in the resource pool for the SL-PRS; and

in the case that the slot includes the resource in the resource pool, SL Control Information (SCI) of the slot is decoded by the UE using a first format for the SL-PRS.

2. The method of claim 1, further comprising: decoding, by the UE, the SCI using a second format for a Physical SL Shared Channel (PSSCH) in the case that the slot does not include the resources in the resource pool.

3. The method of claim 1, wherein the resource pool is configured or preconfigured via Radio Resource Control (RRC) signaling.

4. The method of claim 1, wherein decoding the SCI using the first format indicates time and frequency resource allocation information for the SL-PRS including a SL-PRS resource element offset and a comb size in a frequency domain, a starting symbol and a symbol length of the SL-PRS in a time domain.

5. The method of claim 1, wherein the SCI is in a Physical SL Control Channel (PSCCH) portion of the slot, and the PSCCH portion occupies a first two symbols or a first three symbols of the slot.

6. The method of claim 5 wherein a portion of the SCI is in a SL-PRS portion of the slot and symbols comprising the portion of the SCI are multiplexed in time with SL-PRS symbols.

7. The method of claim 5, wherein the PSCCH portion is repeated in a frequency domain of the slot.

8. The method of claim 7, wherein the transmission power of symbols comprising the PSCCH portion and repetition of the PSCCH portion is equal to the transmission power of other symbols in the slot.

9. The method of claim 1, wherein a first symbol at a beginning of the slot is used for Automatic Gain Control (AGC) training of the SL-PRS, and the first symbol is a repetition of a first SL-PRS symbol or a repetition of a first PSCCH symbol.

10. The method of claim 1, wherein resources of the slot are shared by a plurality of UEs.

11. A method for Side Link (SL) positioning, comprising:

determining, by a User Equipment (UE), a resource pool for receiving SL Positioning Reference Signals (PRS); and

receiving, at the UE, a positioning slot comprising resources in the resource pool;

wherein the positioning time slot comprises:

a first resource of one or more symbols for Physical SL Control Channel (PSCCH) transmission spanning a first subcarrier of the positioning slot; and

and a second resource for the SL-PRS in an area of the positioning slot corresponding to a Physical SL Shared Channel (PSSCH) resource in a non-positioning slot, wherein the second resource spans a bandwidth of the positioning slot.

12. The method of claim 11, wherein the positioning slot further comprises a third resource for repetition of the PSCCH transmission and spanning the one or more symbols of a second subcarrier of the positioning slot, wherein a combination of the first subcarrier and the second subcarrier spans a bandwidth of the positioning slot.

13. The method of claim 12, wherein a first transmission power of a first symbol comprising the SL-PRS matches a second transmission power of a second symbol comprising the PSCCH transmission and a repetition of the PSCCH transmission.

14. The method of claim 11, wherein a symbol at a beginning of the positioning slot is used for Automatic Gain Control (AGC) training of the SL-PRS and the symbol is a repetition of a first SL-PRS symbol or a repetition of a first PSCCH symbol.

15. The method of claim 11, wherein the positioning slot further comprises: a guard time symbol following the second resource for the SL-PRS.

16. The method of claim 11, wherein the PSCCH transmission comprises SL Control Information (SCI) associated with the SL-PRS.

17. The method of claim 16, wherein the SCI indicates resource allocation information for the SL-PRS in the positioning slot.

18. The method of claim 16, wherein the positioning slot further comprises a fourth resource, wherein the fourth resource carries a portion of the SCI not included in the PSCCH transmission.

19. The method of claim 11, wherein resources of the positioning slot are shared by a plurality of UEs.

20. A User Equipment (UE), comprising:

a processor; and

a non-transitory computer-readable storage medium storing instructions that, when executed, cause the processor to:

determining a resource pool for receiving Side Link (SL) Positioning Reference Signals (PRSs);

receiving a time slot;

determining whether the slot includes resources in the resource pool for the SL-PRS; and

in the case that the slot includes the resource in the resource pool, SL Control Information (SCI) of the slot is decoded using a first format for SL-PRS.