Side link positioning

Abstract

A system, method, and apparatus for wireless communication are described. The wireless communication method includes transmitting, by a wireless device, a sidelink positioning reference signal (SL-PRS) over SL-PRS resources, the SL-PRS resources being in a SL-PRS resource pool. The method further includes performing, by the wireless device, sidelink positioning. The described techniques may be employed by a network device or a wireless device.

Description

[Technical field]

[0001] This patent document relates generally to digital wireless communications. [Background technology]

[0002] background Mobile communication technologies are moving the world towards an increasingly connected and networked society. Compared to existing wireless networks, next generation systems and wireless communication technologies will be required to support a much broader range of use case characteristics and provide a more complex and sophisticated range of access requirements and flexibility.

[0003] Long Term Evolution (LTE) is a wireless communications standard for mobile devices and data terminals developed by the 3rd Generation Partnership Project (3GPP®). LTE Advanced (LTE-A) is a wireless communications standard that extends the LTE standard. The fifth generation of wireless systems, known as 5G, is dedicated to advancing the LTE and LTE-A wireless standards to support higher data rates, a large number of connections, ultra-low latency, high reliability, and other emerging business needs. Summary of the Invention [Means for solving the problem]

[0004] overview Techniques are disclosed for performing sidelink positioning. Sidelink is direct device-to-device communication.

[0005] A first exemplary wireless communication method includes transmitting, by a wireless device, a sidelink positioning reference signal (SL-PRS) over SL-PRS resources, the SL-PRS resources being in a SL-PRS resource pool. The method further includes performing, by the wireless device, sidelink positioning.

[0006] A second example wireless communication method includes receiving, by a network device, a sidelink (SL) related information request. The method further includes transmitting, by the network device, a SL related information report or a SL related information update in response to the SL related information request.

[0007] A third exemplary wireless communication method includes detecting, by a wireless device, a sidelink positioning reference signal (SL-PRS) configuration within a detection window. The method further includes selecting, by the wireless device, a SL-PRS resource within a selection window based on the detected SL-PRS configuration.

[0008] In yet another exemplary embodiment, a device configured or operable to perform the above-mentioned method is disclosed. The device may include a processor configured to implement the above-mentioned method.

[0009] In yet another exemplary implementation, the methods described above are embodied in the form of processor executable code and stored in a non-transitory computer readable storage medium, the code contained in the computer readable storage medium, when executed by a processor, causes the processor to perform the methods described in this patent document.

[0010] These and other aspects and their implementations are described in more detail in the drawings, specification, and claims. [Brief description of the drawings]

[0011] [Figure 1] FIG. 1 illustrates an exemplary user equipment (UE) positioning.

[0012] [Diagram 2] FIG. 2 shows an example sidelink (SL) data pool and SL positioning reference signal (SL-PRS) pool configuration. [Diagram 3]FIG. 3 shows an example sidelink (SL) data pool and SL positioning reference signal (SL-PRS) pool configuration.

[0013] [Figure 4] FIG. 4 illustrates an example resource pool hopping.

[0014] [Diagram 5] FIG. 5 illustrates an example resource pool extension.

[0015] [Figure 6] FIG. 6 illustrates an example hybrid UE positioning.

[0016] [Figure 7] FIG. 7 illustrates an example SL configuration transfer between a gNodeB (gNB) and a Location Management Function (LMF). [Figure 8] FIG. 8 illustrates an example SL configuration transfer between a gNodeB (gNB) and a Location Management Function (LMF).

[0017] [Figure 9] FIG. 9 shows example bit sizes of SL-PRS sequences. [Figure 10] FIG. 10 shows exemplary bit sizes of SL-PRS sequences.

[0018] [Figure 11] FIG. 11 illustrates an example slot structure within a SL-PRS resource pool.

[0019] [Figure 12] FIG. 12 shows an example physical sidelink control channel (PSCCH) for indicating / reserving SL-PRS resources.

[0020] [Figure 13] FIG. 13 illustrates an exemplary SL-PRS time and frequency resource allocation indicated in the control information. [Figure 14] FIG. 14 illustrates an exemplary SL-PRS time and frequency resource allocation indicated in the control information. [Figure 15] FIG. 15 illustrates an exemplary SL-PRS time and frequency resource allocation indicated in the control information. [Figure 16] FIG. 16 illustrates an exemplary SL-PRS time and frequency resource allocation indicated in the control information. [Figure 17] FIG. 17 illustrates an exemplary SL-PRS time and frequency resource allocation indicated in the control information.

[0021] [Figure 18] FIG. 18 shows an exemplary SL-PRS detection and selection window. [Figure 19] FIG. 19 shows an exemplary SL-PRS detection and selection window. [Figure 20] FIG. 20 shows an exemplary SL-PRS detection and selection window. [Figure 21] FIG. 21 shows an exemplary SL-PRS detection and selection window. [Figure 22] FIG. 22 shows an exemplary SL-PRS detection and selection window.

[0022] [Diagram 23] FIG. 23 shows an exemplary comb offset pattern.

[0023] [Figure 24] FIG. 24 is an exemplary flow chart for performing SL positioning.

[0024] [Diagram 25] FIG. 25 is an exemplary flow chart for receiving and transmitting SL related information.

[0025] [Figure 26]FIG. 26 is an example flow chart for detecting and selecting a SL-PRS resource.

[0026] [Figure 27] FIG. 27 illustrates an example block diagram of a hardware platform that may be part of a network or communication device.

[0027] [Figure 28] FIG. 28 illustrates an example wireless communication including a base station (BS) and a user equipment (UE) according to some implementations of the disclosed technology. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0028] Detailed Description The exemplary headings of the various sections below are used to facilitate understanding of the disclosed subject matter and are not intended to limit the scope of the claimed subject matter in any way. Thus, one or more features of one exemplary section may be combined with one or more features of another exemplary section. Furthermore, although 5G terminology is used for clarity of description, the technology disclosed herein is not limited to only 5G technology and may be used in wireless systems implementing other protocols.

[0029] I. Introduction

[0030] In the current technology, the UE can perform positioning with the NW over the uu interface by transmitting SRS signals and receiving PRS signals. However, the UE may also need to acquire its accurate location when the UE is out of the coverage of the NW, or even when the UE is in the coverage of the NW but the channel quality is rather low. Sidelink technology fits the case and can be applied for V2X UE to perform positioning. However, in the current specification, the sidelink technology only focuses on how to transmit control signaling and service data over the PC5 interface. In this patent, methods and procedures of signaling transfer for specifying sidelink positioning are provided, including SL-PRS resource pool design, sidelink configuration transfer between the LMF and gNB, SL-PRS sequence generation, SPCI reserved SL-PRS, periodic SL-PRS and scheme 2 SL-PRS allocation / selection.

[0031] Approved SI in RAN#94 for Rel-18 Positioning

[0032] Study and evaluate the performance and feasibility of potential solutions for SL localization considering relative positioning, ranging and absolute positioning: [RAN1, RAN2]

[0033] Evaluate the bandwidth requirements necessary to meet the identified accuracy requirements [RAN1]

[0034] Research into positioning methods (e.g., TDOA, RTT, AOA / D, etc.) that involve the combination of SL positioning measurements with other RAT-dependent positioning measurements (e.g., Uu-based measurements) [RAN1]

[0035] Study of sidelink reference signals for positioning purposes, including signal design, resource allocation, measurements and associated procedures from a physical layer perspective, including reuse of existing reference signals, procedures etc. from sidelink communications and positioning wherever possible [RAN1]

[0036] Study of positioning architecture and signaling procedures (e.g. configuration, measurement reporting, etc.) to enable sidelink positioning covering both UE-based and network-based positioning [including coordination and harmonization with RAN2, RAN3 and SA2 where necessary]

[0037] NOTE: As bandwidth requirements are determined and studies of sidelink communications in unlicensed spectrum proceed, further work may consider whether unlicensed spectrum can be considered. A checkpoint in RAN#97 to see if sufficient information is available for this consideration.

[0038] Sidelink (SL) communication refers to wireless radio communication between two or more user equipments (UEs). In this type of communication, two or more UEs in geographical proximity to each other can communicate without being routed to a base station (BS) or core network. Thus, data transmission in SL communication differs from typical cellular network communication, which involves transmitting data to a BS (e.g., uplink transmission) and receiving data from a BS (e.g., downlink transmission). In SL communication, data is transmitted directly from a source UE to a target UE, for example, over a unified air interface (e.g., PC5 interface), without passing through a BS.

[0039] In the current specification for sidelink communication, both resource allocation mode 1 and mode 2 are supported, where the gNB schedules sidelink resources for the UE in mode 1 and the UE autonomously selects resources for mode 2 (contention-based scheme). The UE may be configured by higher layers with one or more sidelink resource pools. A sidelink resource pool may be for transmission of PSSCH or for reception of PSSCH and may be associated with either sidelink resource allocation mode 1 or sidelink resource allocation mode 2.

[0040] In the frequency domain, the sidelink resource pool consists of (1..27) consecutive subchannels. A subchannel consists of {n10, n12, n15, n20, n25, n50, n75, n100} consecutive PRBs. Both the number of subchannels per resource pool and the subchannel size are higher layer parameters. In the time domain, the sidelink resource pool consists of N subchannels (configured for S-SS / PSBCH blocks [S-SSB]). SSB slots and N (not semi-statically configured as UL) nonSL The set of slots that may belong to the sidelink resource pool excluding this slot and the reserved slots. After the bit mapping, a set of slots ("logical slot set") is determined and assigned to the sidelink resource pool.

[0041] In Rel-15 / 16, the location of the target UE can be determined using reference signals (downlink signal PRS / uplink signal SRS) transmitted between the UE and the gNB / ng-eNB to obtain the location information of the target UE. Figure 1 shows the architecture in 5GS, which is specified in TS38.305 and applicable to positioning of UEs with NR or E-UTRA access.

[0042] The UE in this patent can be a vehicular UE, or a pedestrian UE, or an RSU (Roadside Unit) with or without a known location, or a PRU (Positioning Reference Unit) with or without a known location, or any UE that supports V2X services and / or sidelink communication.

[0043] Also, in this patent, the suffix "based" refers to the node that is involved in making the positioning calculation (and may provide measurements).

[0044] Hybrid positioning (joint SL and Uu positioning) method: One or more UEs perform sidelink measurements and location / ranging is estimated using measurements derived from both sidelink and Uu positioning, applies to in-coverage and / or partial coverage scenarios.

[0045] High-precision positioning requires large bandwidth. If the SL-PRS is configured in the same way as the current sidelink RS within the frequency range of the PSSCH, it is difficult to meet the positioning requirements. Therefore, a solution / method for wide-bandwidth SL-PRS configuration needs to be considered.

[0046] The SL-PRS resource pool in this patent may be a dedicated SL-PRS resource pool (detailed design is shown in embodiment 1) or a shared resource pool (detailed design is shown in embodiment 2, configuring SL-PRS in sidelink communication pool).

[0047] Embodiment 3 can answer the questions of who configures the SL-PRS and who distributes / allocates SL-PRS resources.

[0048] Embodiment 4 mainly focuses on SL-PRS sequence design, and several equations / formulas / solutions are provided for the SL-PRS sequence initialization function.

[0049] In relation to embodiment 1, SL-PRS triggered / reserved by control information (e.g., SPCI) (detailed design is shown in embodiment 5) and / or periodic SL-PRS (details are shown in embodiment 6) can be considered for a dedicated SL-PRS resource pool.

[0050] Embodiment 5 includes a design of an SPCI-triggered / reserved SL-PRS, including a slot structure, a time / frequency resource of the SPCI, and a field content of the SPCI.

[0051] Embodiment 6 focuses on the design of detection and selection windows for periodic SL-PRS.

[0052] Embodiment 7 considers how to select SL-PRS resources based on the sensing result.

[0053] II. Embodiment 1

[0054] Dedicated SL-PRS Resource Pool

[0055] Dedicated SL-PRS resource pool: The SL-PRS can be (pre-)configured separately from the SL communication pool. Regarding the multiplexing of the dedicated SL-PRS resource pool and the SL communication resource pool, at least one of the following options can be selected:

[0056] Case 1. TDM between a dedicated SL-PRS resource pool and a SL communication resource pool

[0057] Case 2. Resource pool time / frequency is up to configuration

[0058] A UE may be (pre)configured by higher layers with one or more SL-PRS resource pools. As shown in Figure 2, SL-PRS and SL data belong to the same BWP but to different resource pool configurations. Each pool / configuration may occupy a portion of the BWP resources including time and frequency resources. A sidelink resource pool may be for transmission of SL-PRS or for reception of SL-PRS and may be associated with either SL-PRS resource allocation scheme 1 or SL-PRS resource allocation scheme 2.

[0059] Scheme 1 SL-PRS resource pool: indicates the resources / configuration on which a UE is allowed to transmit SL-PRS based on network scheduling on a configured BWP.

[0060] Scheme 2 SL-PRS resource pool: indicates the resources / configuration on which a UE is allowed to transmit SL-PRS via UE autonomous resource selection on a configured BWP.

[0061] Alternatively, as shown in Figure 3, the UE may be (pre)configured by higher layers with only one SL-PRS resource pool. Each SL-PRS resource pool consists of one or more SL-PRS configurations (e.g. time frequency resources, power control CBR, PSCCH, IUC, comb pattern, number of symbols, repetition, periodicity, muting pattern, SL-PRS resource ID, SL-PRS sequence ID). Different SL-PRS configurations may be selected by higher layers (UE higher layers, or gNB via RRC / DCI, LMF via LPP signaling) based on different location services, or the UE has its pre-configured / default SL-PRS configuration.

[0062] Case 1

[0063] To support pool-level TDM, the following time-domain and frequency-domain designs should be used: For maximum resource utilization, different SL-PRS resource pools are not restricted to TDM or FDM.

[0064] Regarding time resources in the dedicated SL-PRS resource pool:

[0065] A "logical slot set" for a SL-PRS, the set of slots that may belong to a SL-PRS resource pool other than at least one of the following:

[0066] N S-SSB slots (configured for S-SS / PSBCH block [S-SSB])

[0067] N nonSL slots (not semi-statically configured as UL)

[0068] The set of slots N that are determined and assigned to the sidelink resource pool (after the bit mapping "sl-TimeResource-r16 BIT STRING(SIZE(10..160))") mapped .

[0069] The "logical slot set" of the SL-PRS is the reserved slot N of the SL communication pool. reserved and / or slot N non-mapped N S-SSB slots, N nonSL These slots, as well as the reserved slots, are excluded but are not assigned to the sidelink resource pool according to the bitmap (sl-TimeResource-r16).

[0070] A sidelink communications resource pool consists of a set of time and frequency resources. A "logical slot set" for SL data, reserved slots, bitmaps are configured for each sidelink communications resource pool. In other words, each sidelink communications resource pool is composed of N non-mapped pcs and N reserved slots. A UE can be (pre-)configured by higher layers with one or more SL-PRS resource pools and multiple UEs can be involved in SL related communications. To ensure pool-level TDM, the SL-PRS resource pool must not overlap with the SL communications resource pool.

[0071] Alternative 1: Depends on gNB or LMF configuration and / or higher layer (pre) configuration of the UE.

[0072] Alternative 2: The UE may initially broadcast resource pool information / configuration including time resources of the SL communication pool. With knowledge of the SL resource allocations of other UEs, it is possible to select one TDM SL-PRS resource pool.

[0073] Regarding frequency resources in the dedicated SL-PRS resource pool:

[0074] Shares the same BWP and carrier as the SL communication resource pool

[0075] SL-PRS Frequency Resource Granularity

[0076] Reusing Subchannels

[0077] Subchannels may not be required: SL-PRS may occupy all or any number of available RBs in one SL-PRS resource pool (details are described in the last paragraph of embodiment 1)

[0078] A frequency resource consists of a set of contiguous RBs.

[0079] The following parameters may be configured per SL-PRS resource pool by the gNB in ​​RRC or by the LMF via LPP signaling:

[0080] Indicates that RB + start RB number, or start RB + end RB, or all RBs in the BWP, or all RBs in the carrier frequency are occupied

[0081] Or the number of subchannels per resource pool, the subchannel size, and the starting RB, if necessary, the RB number in the SL-PRS resource pool

[0082] Case 2

[0083] If a resource pool for sidelink communication and a dedicated resource pool for SL-PRS multiplexed in TDM mode are applied, the positioning delay may become large. reservedThe distribution principle of is discrete and evenly distributed in the SFN / DFN cycle (10240 ms), and the interval between two reserved slots can be very large. In addition, if the SL-PRS resource pool does not overlap with any SL communication resource pool to ensure pool-level TDM, the slots available for SL-PRS are limited. Therefore, this type of SL-PRS resource pool design is more suitable for services that do not require high positioning delay or low-speed UEs.

[0084] From the perspective of delay reduction and positioning accuracy, a dedicated SL-PRS resource pool can be designed up to a higher layer configuration (not limited by TDM scheme using SL communication resource pool).

[0085] About time resource configuration of SL-PRS resource pool

[0086] It may overlap with SL data and share the same / similar time logic slots as SL data.

[0087] Indicates the priority threshold used to determine whether a SL-PRS transmission / pool / configuration / symbol / slot / resource is prioritized over an uplink / SL data transmission / pool / configuration / symbol / slot / resource.

[0088] The priority may be indicated by higher layer signaling (e.g., RRC, LPP) and / or lower layer (e.g., DCI, SCI, SPCI (Sidelink Positioning Control Information), MAC CE) signaling.

[0089] Frequency resource configuration of SL-PRS resource pool

[0090] Consecutive RBs

[0091] SL-PRS Frequency Resource Granularity

[0092] Reusing Subchannels

[0093] Subchannels may not be required: SL-PRS may occupy all or any number of available RBs in one SL-PRS resource pool (details are described in the last paragraph of embodiment 1)

[0094] With respect to a SL-PRS resource pool associated with either SL-PRS resource allocation scheme 1 or SL-PRS resource allocation scheme 2, at least one of the following may be considered:

[0095] The SL-PRS scheme 1 resource pool and scheme 2 resource pool will have no resource contention, which is up to pre-configuration or gNB / LMF configuration.

[0096] There may be overlap in time / frequency resources between the SL-PRS resource pools associated with the two schemes.

[0097] Solution 1: Check that the priority of SL-PRS in scheme 1 is higher than the priority of SL-PRS in scheme 2. If so, when a resource conflict with a scheme 2 UE is detected / sensed by the scheme 1 UE, the scheme 2 UE will exclude those / conflicting SL-PRS resources reserved / triggered by the scheme 1 UE.

[0098] Per-pool priority: Used to determine whether NR SL-PRS transmissions in scheme 1 are prioritized over SL-PRS transmissions in scheme 2.

[0099] The SCI / SPCI indicates scheme 1 or scheme 2. If the UE receives a SL-PRS configuration from the gNB via DCI / RRC / MAC CE or receives LPP signaling from the LMF, the SCI may include a scheme indicator. The scheme indicator may occupy only one bit, e.g., 0 for scheme 2 and 1 for scheme 1.

[0100] Solution 2: A UE in SL-PRS resource allocation scheme 1 may also need to transmit SL-PRS after detection. After detection, the UE may send its detection result to the gNB and / or LMF, and the gNB and / or LMF may further determine the SL-PRS resource.

[0101] The SL-PRS resource pool may be configured by the gNB and / or the LMF. At least one of the following parameters may be configured within / per SL-PRS resource pool:

[0102] 1. SL-PRS resource pool configuration: time resources, frequency resources, and priorities

[0103] 2. SL-PRS configuration: UE information (ID of UE in positioning session, source ID destination ID), SL PRS resource set / SL PRS resource configuration, SL PRS resource set / SL PRS resource list, SL PRS resource set / SL PRS resource ID, periodicity of SL PRS resource / SL PRS resource set, number of symbols occupied by SL PRS in slot, starting symbol of SL PRS in slot, SL PRS resource frequency location and bandwidth, SCS, comb size, RE offset, muting pattern, SL-PRS QCL information, periodic / semi-persistent / non-periodic SL PRS, priority of SL PRS resource / SL PRS resource set, SL-PRS sequence ID, SL-PRS resource cyclic prefix length, repetition time gap between two repetition instances of SL-PRS, SL-PRS repetition factor, slot offset.

[0104] 3. Control information for SL-PRS (e.g., PSCCH / SPCI) configuration: time resource for SPCI, frequency resource for SPCI

[0105] 4. Synchronization References: Indicates the allowed synchronization references that are allowed to use the configured SL-PRS resource pool.

[0106] 5. Scheme / Mode 2 Configuration: CBR configuration and its association relationship with SL-PRS transmission parameters, maximum number of reserved SL-PRS resources that can be indicated by an SPCI, whether sidelink resources can be reserved for initial transmission of a TB by an SPCI associated with a different TB, SL-PRS resource reservation period, detection window, selection window, SL-PRS RSRP threshold, SL-PRS RSRP threshold.

[0107] 6. Power control configuration: e.g., maximum SL-PRS transmit power, alpha value and P0 value for either sidelink path loss based power control or downlink path loss based power control.

[0108] Frequency domain configurations for both Case 1 and Case 2 (subchannel related):

[0109] When the subchannel concept is used, similar designs for SCI frequency resources, FRIV, SL CR definition, SL CBR, SL RSSI, transmission parameters can be applied to SL-PRS.

[0110] Otherwise, the granularity SPCI frequency resource, FRIV, SL-PRS CR, SL-PRS CBR, SL-PRS RSSI, SL-PRS transmission parameters can be defined as one or more PRBs.

[0111] III. Embodiment 2

[0112] Shared Resource Pool for SL-PRS

[0113] Alternatively, the SL-PRS resources can be configured in a SL communication resource pool (SL-ResourcePool), in other words, the SL-PRS and SL data transmission / reception share the same resource pool and the same logical slot set. To achieve high-precision positioning, an expanded SL-PRS frequency resource is needed for SL positioning. At least one of the following solutions can be used:

[0114] Case 1: Use "remaining PRB" for SL-PR

[0115] According to the following table specified in TS38.331, the granularity of the frequency resources of the SL resource pool is a subchannel, and each SL resource pool consists of "sl-NumSubchannel" consecutive subchannels, and one subchannel contains "sl-SubchannelSize" consecutive PRBs. However, the RRC parameter "sl-RB-Number" also indicates the number of PRBs in the corresponding resource pool, and sl-NumSubchannel*sl-SubchannelSize is not always equal to sl-RB-Number. Therefore, there are still some PRBs that cannot be used for PSCCH / PSSCH. [ka]

[0116] For SL-PRS configuration in the frequency domain, the maximum number of PRBs for SL-PRS resources can be up to sl-RB-Number. Specifically, if the remaining RBs are used by SL-PRS resources, the SCI may indicate whether these PRBs are configured / used by SL-PRS and the number of remaining PRBs in addition to the starting subchannel index and the number of subchannels. The start of the remaining PRBs is the ending PRB of the PSSCH resource in the resource pool.

[0117] Case 2: Resource Pool Hopping

[0118] As shown in Figure 4, it is not shared with one SL data pool, but is associated / shared with several SL data pools. There is an association relationship between the SL-PRS resource pool and one or more SL data resource pools.

[0119] The SL-PRS resources transmitted in different SL resource pools may partially overlap depending on the frequency range of each resource pool. The random phase rotation between two hops can be resolved by the overlapping frequency resources.

[0120] If specific instructions are required, at least one of the following may be used:

[0121] One or more SL resource pool index indication: In scheme / mode 1, DCI / RRC / LPP signaling may indicate one or more SL resource pool indexes to the UE. Each SL resource pool requires a time gap and time / frequency resource allocation. In scheme / mode 2, higher layers in the UE are responsible.

[0122] SL resource pool group list indication: The group list may be configured by the gNB and / or LMF via DCI / RRC / LPP signaling or may be pre-configured. Both Tx UE and Rx UE should be informed of the SL resource pool group information. For example, the Rx UE may aggregate some SL-PRS resources with the same group ID.

[0123] Within each resource pool group, the gNB or LMF or UE may also report a resource pool index within the group.

[0124] For SL-PRS resources within a group of SL resource pools or one or more (pre-)configured SL-PRS resource pools, at least one or more of the following parameters should be the same to ensure that the receiver side can combine multiple SL-PRS resources from different SL resource pools:

[0125] S.C.S.

[0126] Comb Size

[0127] Comb Offset

[0128] UE information (e.g. UE ID, source ID, destination ID)

[0129] SL-PRS sequence ID

[0130] SL-PRS Resource Bandwidth

[0131] CP type

[0132] SL-PRS Periodicity and Slot Offset

[0133] SL-PRS Resource Repetition

[0134] SL-PRS Resource Time Gap

[0135] The number of symbols that the SL PRS occupies in a slot

[0136] Starting symbol of SL PRS in slot

[0137] SL PRS Resource Frequency Location and Bandwidth

[0138] Muting Pattern

[0139] SL-PRS QCL Information

[0140] A switching gap between the SL-PRS resources in the two SL-PRS resource pools may be required.

[0141] An SCI is required for each SL resource pool (SCI1 in SL resource pool 1, SCI2 in SL resource pool 2, and SCI3 in SL resource pool 3).

[0142] From the UE side, the UE needs to report its capability to the LMF or gNB to support frequency / resource pool hopping. The UE can also report its capability to the LMF or gNB to support overlap between two frequency / resource pool hops.

[0143] On the receiver side, the UE can combine linked SL-PRS resources from one or more pools or resource pool groups to obtain a combined measurement result. The UE combines linked SL-PRS resources in the frequency domain, and measurements based on linked SL-PRS resources from one or more pools or resource pool groups are equivalent to a larger bandwidth measurement.

[0144] On the receiver side, the UE needs to report the measurement results with a SL resource pool group index or with one or more SL resource pool indexes. If the UE reports only one SL resource pool (group) ID, it means that the UE does not combine measurements from multiple SL resource pools.

[0145] Case 3: Extending SL-PRS outside the SL resource pool in the frequency domain

[0146] As shown in FIG. 5, the maximum PRB number of the SL-PRS configuration in the SL communication resource pool can be greater than "sl-RB-Number".

[0147] SCI format 1-A may need to indicate frequency resource allocation for the SL-PRS.

[0148] The starting and ending PRB index / PRB number of the PRB index of the SL-PRS resource.

[0149] Or the starting subchannel index and the number of subchannels

[0150] Alternatively, a second stage SCI (either an existing second stage SCI or a new second stage SCI format) may be used to trigger / reserve SL-PRS transmission resources.

[0151] IV. Embodiment 3

[0152] Sidelink configuration transfer between LMF and gNB

[0153] For the study of sidelink positioning, in-coverage, out-of-coverage and partial coverage scenarios need to be considered. Both network-based and UE-based positioning methods can be supported. The network can be involved in SL-PRS configuration or / and assistance data transmission or / and position calculation etc. for sidelink positioning. In case of network-based positioning, the UE may report the necessary information for calculation to the network (including gNB and LMF etc.). UE-based positioning refers to a solution where the UE position is calculated by the UE.

[0154] As shown in FIG. 6, according to the 5G NR Uu positioning architecture, the LMF may interact with the target UE (via LPP) to deliver assistance data or obtain a location estimate, and the LMF may also interact with the serving gNB or serving ng-eNB for the target UE to obtain location measurements of the UE, and further, the LMF can determine the positioning method based on the UE positioning capabilities and gNB / ng-eNB information reports and other factors.

[0155] For the design of NG-RAN UE SL positioning architecture, the LMF should also be part of the sidelink positioning to manage the support of different location services for the target UE. In particular, when a UE in one positioning session has more than one serving NG-RAN node (e.g., gNB), the LMF needs to be used to interact with multiple NG-RAN nodes for assistance data information, NG-RAN node capabilities, and location information. In addition, hybrid positioning can be supported to further improve the positioning accuracy by combining measurements derived in both SL positioning and Uu positioning. The assistance data transmitted from the LMF to the UE may include both DL-PRS-related information and SL-PRS-related information. The LMF may also collect both SL and Uu measurements to calculate the UE's location.

[0156] However, current sidelink communication does not require the participation of the LMF, and obviously, the LMF does not have sidelink related information. To support the involvement of the LMF for sidelink positioning and hybrid positioning, sidelink related information transfer between the LMF and the gNB should be supported, as shown in Figure 7. Sidelink related information can be conveyed at least in one of the following ways:

[0157] New / separate NRPPa messages

[0158] Support Data

[0159] The purpose of the procedures between the LMF and the gNBs is to enable one or more gNBs to provide sidelink related information to the LMF, as shown in Figure 8, for use in the calculation of positioning estimates in the LMF, or to enable the LMF to request sidelink communication or SL-PRS configuration information from the serving gNB of the target UE.

[0160] Specifically, the LMF requires information of time and frequency resources available for sidelink transmission and / or reception (SL data, SL-PRS). The requested sidelink related information transmitted from the LMF to the gNB may include at least one of the following:

[0161] TRP ID

[0162] UE SL-PRS configuration

[0163] Response Time

[0164] Sidelink related information reporting types: triggered reporting, periodic reporting, condition-based reporting (e.g., the LMF requests the gNB to report sidelink related configurations every time the configuration changes)

[0165] UE identity: The LMF may inform the gNB about the identities of several UEs included in one positioning session.

[0166] The sidelink related information transmitted from the gNB to the LMF may include at least one of the following:

[0167] gNB Information

[0168] PCI, GCI, ARFCN and TRP ID of TRPs served by gNB

[0169] Timing information for TRPs served by gNBs

[0170] TRP Type

[0171] Sidelink communication resource configuration configured by each gNB

[0172] UE Information

[0173] Sidelink communication resource pool index for the UE

[0174] Tx Resource Pool

[0175] Rx Resource Pool

[0176] Mode 1 Resource Pool

[0177] Mode 2 Resource Pool

[0178] Exceptional Resource Pool

[0179] Time resources for each sidelink communication resource pool

[0180] A "logical slot set" for one sidelink communication resource pool

[0181] Frequency resources for each sidelink communication resource pool

[0182] Frequency resource location: subchannel size, starting RB, number of subchannels, RB number

[0183] SL-PRS resource configuration configured by each gNB

[0184] UE SL-PRS resource pool index

[0185] Tx Resource Pool

[0186] Rx Resource Pool

[0187] Scheme 1 resource pool: indicates the resources that a UE is allowed to transmit SL-PRS on the configured BWP based on network scheduling.

[0188] Scheme 2 resource pool: indicates the resources on which a UE is allowed to transmit SL-PRS via UE autonomous resource selection on a configured BWP.

[0189] Exceptional Resource Pool

[0190] Time resources for each SL-PRS resource pool

[0191] A "logical slot set" for one SL-PRS resource pool

[0192] Frequency resources for each SL-PRS resource pool

[0193] Frequency resource location

[0194] At least one of the following options may be considered:

[0195] Option 1: LMF sends SL-PRS related configuration to UE

[0196] Alternative 1: Multiple gNBs involved in one positioning procedure / session (gNBs serving a particular UE) send the UE's configured SL communication resource pool information to the LMF. It is up to the LMF how to configure the SL-PRS resource pool / resources.

[0197] Alternative 2: Multiple gNBs involved in one positioning procedure / session (gNBs serving a particular UE) send the UE's configured SL-PRS resource pool information to the LMF. The LMF can further inform the UE of the SL-PRS resource pool / resources / configuration.

[0198] Alternative 3: Multiple gNBs involved in one positioning procedure / session (gNBs serving a particular UE) send the UE's configured SL-PRS resource information and SL communication resource pool related information to the LMF. The LMF can further inform the UE of the SL-PRS resource pool / resources / configuration.

[0199] The SL-PRS related configuration may be transmitted to the UE via LPP signaling, for example, assistance data.

[0200] SCI or MAC CE, PC5 RRC can be used to indicate SL-PRS resources / configuration / pool index / characteristics between UEs or transmitted from UE to UE via SL-PRS sequence only.

[0201] Option 2: gNB sends SL-PRS related configuration to UE

[0202] The gNB may first transmit the SL-PRS related configuration to the LMF and ask for confirmation. The LMF may decide whether the SL-PRS is transmitted and may change the characteristics / configuration / pool / resources of the SL-PRS transmission.

[0203] The gNB sends / distributes / allocates SL-PRS pool / resources / configuration to the UE

[0204] Signaling from the gNB to the UE can be either RRC or RRC and MAC CE(Uu), or RRC and DCI.

[0205] UE to UE signaling can be via either the SCI or MAC CE, or just the SL-PRS sequence.

[0206] Multiple gNBs involved in one positioning procedure / session (gNBs serving a particular UE) send the UE's configured SL-PRS resource pool information to the LMF, which can further use this information to calculate / estimate the location.

[0207] The UE may report its SL-PRS resource pool information to the LMF.

[0208] Furthermore, a timestamp specifying the time instance at which a measurement is performed or a particular signal is received or transmitted is essential for positioning. The slot index used in sidelink communication is based on a "logical slot set" to access absolute timing (e.g., the slot index is relative to slot #0 of the radio frame corresponding to SFN0 or DFN0 of the serving cell) and to support LMF-based SL positioning, and at least one of the following may be considered:

[0209] For measurement reports from the UE to the LMF, the timestamp and / or slot index are absolute timing.

[0210] The gNB or UE reports the UE's configured SL-PRS resource pool information to the LMF. In such a case, the UE may report only the timestamp and / or slot index based on the SL-PRS "logical slot set".

[0211] V. Embodiment 4

[0212] Sequence Design

[0213] To meet the positioning accuracy requirements, reduce the complexity, and obtain better multiplexing between the SL-PRS and other signals, the Gold sequence is preferred considering that it is also used for both DL-PRS and reference signals (e.g., sidelink CSI-RS design) in SL communication. The sequence r(m) of the SL-PRS can be generated as follows:

[0214] [ka]

[0215] The pseudo-random sequence generator for DL-PRS and sidelink CSI-RS shall be initialized (according to TS 38.211) as follows: [ka]

[0216] In the design sequence generation of SL-PRS, the initialization function design is one of the important factors of the SL-PRS sequence.

[0217] Case 1: SL-PRS Sequence ID-Tx UE Information

[0218] The SL-PRS sequence ID can be associated with UE information, e.g., sequence ID n ID can be set as a source ID, a UE ID, or a pre-configured sequence ID. The source ID (n s-ID ∈{0,1,…,255}) are represented by higher layers.

[0219] A pseudorandom sequence c(i) shall be initialized by:

[0220] [ka]

[0221] Where: [ka] is the slot number in the radio frame, l is the OFDM symbol number in the slot, and n ID is the SL-PRS sequence ID, and m is equal to the bit size of the SL-PRS sequence ID. ID =n s-ID , i.e., for the "source ID" indicated by a higher layer, m is equal to 8. As shown in FIG. 9, there may be low-order bits and high-order bits.

[0222] Case 2: SL-PRS sequence - Rx UE information

[0223] The SL-PRS sequence can be associated with the Rx UE information. The Tx UE and Rx UE information may include the following: Tx UE ID, Rx UE ID, source ID (8 bits), destination / target ID (16 bits), location service type, a pre-configured sequence ID that includes both Tx UE information and Rx UE information. The destination ID configured by the upper layers for NR sidelink communication transmission may include both the Rx UE ID (especially for unicast) and the sidelink service type (especially for broadcast and groupcast).

[0224] A pseudorandom sequence c(i) shall be initialized by:

[0225] [ka]

[0226] Where: [ka] is the slot number in the radio frame, l is the OFDM symbol number in the slot, and n TX-ID is the SL-PRS sequence ID containing Tx UE information, and x is n TX-ID where x is the bit size of x, y is a constant, which may be equal to (32-x) or some other value.

[0227] n RX-ID If the bit size of is larger than x, we can design an offset that occupies higher bits. The initialization function of SL-PRS can be modified as follows:

[0228] [ka]

[0229] As shown in FIG. 10, there may be lower order bits, middle order bits, and upper order bits.

[0230] Case 3: Unique SL-PRS sequence identification

[0231] The SL-PRS sequence ID can be associated with both Tx UE information and Rx UE information. m There are m=(x+z) unique SL-PRS sequence identities.

[0232] [ka]

[0233] or

[0234] [ka]

[0235] where n TX-ID The bit size of is x and n RX-ID The bit size of is z. The Tx UE and Rx UE information may include the following: Tx UE ID, Rx UE ID, source ID (8 bits), destination / target ID (16 bits), location service type, pre-configured sequence ID including both Tx UE information and Rx UE information.

[0236] A pseudorandom sequence c(i) shall be initialized by:

[0237] [ka]

[0238] Where: [ka] is the slot number in the radio frame, and l is the OFDM symbol number within the slot.

[0239] If the bit size of the SL-PRS sequence m is too large, for example, m is greater than m_max, an offset shall be added to the initialization function.

[0240] [ka]

[0241] To be consistent with the sequence design of the DL-PRS, at s=1024, a pseudo-random sequence c(i) may be initialized with:

[0242] [ka]

[0243] Case 4: SL-PRS configuration

[0244] The SL-PRS sequence can be associated with some SL-PRS configuration information. This design is intended to allow periodic SL-PRS (pure higher layer signaling without any lower layer signaling involved). When the Rx UE receives the SL-PRS sequence, some SL-PRS confirmation information (e.g. priority) can be decoded.

[0245] A pseudorandom sequence c(i) shall be initialized by:

[0246] [ka]

[0247] Where: [ka] is the slot number in the radio frame, l is the OFDM symbol number in the slot, and n ID is the SL-PRS sequence ID, and n configis associated with some SL-PRS configuration and occupies the most significant bits. n_c can be equal to either (32-m) or (32-c), where c is n config is the bit size of

[0248] n config may include at least one of the following SL-PRS structures: priority of SL PRS resource / SL PRS resource set, periodicity of SL PRS resource / SL PRS resource set, number of symbols the SL PRS occupies in a slot, comb size, muting pattern, SL-PRS QCL information, synchronization reference, power control configuration.

[0249] n config may be associated with more than one SL-PRS configuration, in which case different SL-PRS configurations (to be included in the SL-PRS sequence) occupy different bits. For example, a priority may occupy the highest / most significant bits in bits n_c to 32, and other configurations occupy the lower bits in bits n_c to 32.

[0250] One or more of the cases (Case 1, Case 2, Case 3, Case 4) can be combined. For example, Case 2 and Case 4 can be combined to include both Rx UE information and SL-PRS configuration.

[0251] VI. Embodiment 5

[0252] SPCI Reservation SL-PRS

[0253] For simplicity, we use SPCI to imply control information for SL positioning.

[0254] In the case of a dedicated SL-PRS resource pool, SPCI-triggered / reserved SL-PRS and / or periodic SL-PRS (details are shown in embodiment 5) may be considered.

[0255] When a UE transmits a SL-PRS, control information may be transmitted along with the SL-PRS resource. Other UEs can then receive the control information of the UE. Based on the SL-PRS resource indicated / associated with the control information, the other UEs can find out whether and where to receive the SL-PRS resource.

[0256] Slot structure of SL-PRS: Each slot contains a SPCI and a SL-PRS (as shown in Figure 11), or one SPCI triggers multiple SL-PRS opportunities / samples (as shown in Figure 12).

[0257] The SPCI is carried on the PSCCH.

[0258] SPCI Time Resources:

[0259] Number of symbols in a slot

[0260] Consider at least one of the following: 1, 2, 3, ... N symbols

[0261] period

[0262] This indicates the periodicity of the PSCCH resources in slot units within this SL-PRS resource pool.

[0263] SPCI frequency resources:

[0264] Number of PRBs:

[0265] Upper limit per resource pool: for example, indicates the number of PRBs for PSCCH in the SL-PRS resource pool, which is less than or equal to the upper limit number of PRBs, and may be the number of PRBs of the subchannels configured in the SL-PRS resource pool if subchannel configuration is supported.

[0266] Specific value: Number of PRBs for PSCCH in the SL-PRS resource pool

[0267] Frequency range: SL-PRS frequency domain resources can be divided into multiple parts / ranges, with each part containing a certain range of frequency resources. For one slot in the SL-PRS resource pool, one or more UEs can transmit SPCI only in one configured frequency part / range.

[0268] Location:

[0269] RRC or LPP signaling may be used to indicate the start RB index and end RB index, or the start RB index and the number of RBs. From the Rx UE's perspective, it is beneficial to reduce the complexity of SCI decoding / detection.

[0270] For sidelink communication, the SCI is carried on both the PSCCH and the PSSCH. The SCI carried on the PSCCH is the first-level SCI carrying sidelink scheduling information. The SCI carried on the PSSCH is the second-level SCI carrying sidelink scheduling information and / or UE coordination related information.

[0271] However, in case of a dedicated SL-PRS resource pool, the two-stage SCI may no longer be required since the SL-PRS are not transmitted in the same resource pool as the SL data carried in the PSSCH. The information carried in the SPCI (Sidelink Positioning Control Information) may include at least one of the following:

[0272] SL-PRS transmission / pool / configuration / symbol / slot / resource priority

[0273] SL-PRS Resource Allocation Scheme 1 / Scheme 2 Indicator

[0274] SL-PRS Frequency Resource Allocation

[0275] SL-PRS Time Resource Allocation

[0276] Next / Subsequent SPCI Time / Frequency Allocations

[0277] SL-PRS resource reservation period

[0278] SL-PRS Pattern / Configuration

[0279] SL-PRS periodicity

[0280] SL-PRS Resource Slot Offset

[0281] SL-PRS Resource Symbol Offset

[0282] SL-PRS iteration

[0283] SL-PRS symbol number for each slot

[0284] SL-PRS Muting Pattern

[0285] SL-PRS Resource Power

[0286] SL-PRS sequence ID

[0287] SL-PRS Comb Size

[0288] SL-PRS Comb RE Offset

[0289] UE information, e.g. source ID

[0290] Destination ID

[0291] SL-PRS request / instruction

[0292] Indicator for the presence or absence of one or more SL-PRS transmissions

[0293] Time limit / validity of one SPCI

[0294] Cast Type

[0295] Zone ID

[0296] Communication range

[0297] Specifically, the SL-PRS time / frequency resource allocation should consider at least the following cases:

[0298] Case 1:

[0299] The SPCI can be used for SL-PRS resource reservation. The "Time Resource Allocation" and "Frequency Resource Allocation" fields of the SPCI are used to indicate the time-frequency resources of the N SL-PRS transmissions in a period / window. The last (N-1) SL-PRS resources are repetitions / retransmissions of the first / initial SL-PRS resources for robust positioning. The length of the period / window and the value of N can be configured by the gNB via RRC and / or DCI, MAC CE, or by the LMF via LPP signaling.

[0300] As shown in Figure 13, the unit "SL-PRS resource reservation period" (p shown in the following figure) can be either "ms" or slots, and this field is used to indicate the SL-PRS resource for the next cycle / period. The value of the SL-PRS resource reservation period can be configured by the gNB via RRC and / or DCI, MAC CE, or by the LMF via LPP signaling. Candidate values ​​of the SL-PRS resource reservation period (which can be in either ms or slots) may include at least one of the following: 1 to 99 (step: 1), 100, 160, 200, 300, 320, 400, 500, 600, 640, 700, 800, 900, 1000, 1280, 2560, 5120, 10240.

[0301] Case 2:

[0302] As shown in Figure 14, the SPCI may indicate the time / frequency location of the first SL-PRS transmission, the SL-PRS periodicity, the time limit / validity time of one SCI, and the time limit or validity time of one SCI may be configured by higher layers of the UE, or by the gNB via RRC and / or DCI, or by the LMF via LPP signaling. In other words, within the time limit / validity time, the SL-PRS resources are transmitted based on the same periodicity, comb size, sequence ID, etc.

[0303] Furthermore, an SPCI may indicate the time / frequency location of the next SPCI, as shown in Figure 15. Two adjacent / consecutive SPCIs may indicate the same or different SL-PRS resources corresponding to the same or different SL-PRS configurations.

[0304] Case 3:

[0305] Similar to case 2, the SPCI may indicate the time / frequency location of the first SL-PRS transmission, the SL-PRS periodicity and other SL-PRS configurations. As shown in FIG. 16, the UE may be configured / informed by the higher layer or LMF or gNB of the UE with several SPCI resources / locations, each SPCI resource having a one-to-one correspondence or association with several SL-PRS configurations. Or, the UE may be configured / informed by the higher layer or LMF or gNB of the UE with several SL-PRS resources / SL-PRS resource sets. Each SPCI may be used to reserve one or more SL-PRS resources, whether they have the same SL-PRS configuration or not. The UE may need another SPCI only if the SL-PRS resources / configuration is to be changed under the conditions of resource contention based on the sensing result or higher layer reconfiguration.

[0306] Case 4:

[0307] The SPCI may also be used to indicate the current SL-PRS transmission resource and the next / subsequent SPCI resource, as shown in Figure 17. The time / frequency location within one slot of the current SPCI and the subsequent reserved SPCI may or may not be the same, but may be different and correspond to the same SL-PRS resource configuration for interference randomization.

[0308] Detection window size for SL-PRS as instructed by SPCI:

[0309] For Cases 2 and 3, the sensing window size should be equal to or greater than the interval between adjacent / consecutive SPCIs, as shown in FIG.

[0310] VII. Embodiment 6

[0311] Periodic SL-PRS

[0312] For periodic SL-PRS transmission, to avoid resource collision, UEs need to first broadcast / unicast / multicast their sequence configuration (which may include UE information) and SL-PRS configuration (e.g., SL-PRS resource / resource set ID, SL-PRS resource / resource set list, time domain transmission / transmission start location, periodicity, repetition, muting pattern, comb pattern, RE offset, priority, start PRB, slot offset, number of symbols per slot, SL-PRS resource power, SL-PRS QCL information, time gap between two repeat instances of SL-PRS corresponding to the same SL-PRS ID, SL-PRS subchannel size, number of subchannels, etc.). A UE can correctly decode the SL-PRS configuration only if it obtains the sequence ID configuration information of other UEs.

[0313] There is a one-to-one correspondence or association between the SL-PRS sequence information and several SL-PRS configurations, which can be configured by the LMF (via RRC and / or DCI, MAC CE) via LPP signaling or via the gNB.

[0314] Scenario 1: As shown in FIG. 19, periodic SL-PRS resources are configured in a dedicated resource pool, and SPCI reserved SL-PRS is not considered.

[0315] Detection and selection window design:

[0316] Detection means detecting a SL-PRS and decoding its sequence ID and its associated SL-PRS configuration.

[0317] The detection window size is related to the SL-PRS periodicity and / or the SL-PRS repetition time gap. The detection window size considers all periodicities configured for the UE in the positioning session, the periodicity being part of the broadcast message. If SL-PRS repetition is supported, the detection window size may consider all repetition time gaps between two repeat instances of the SL-PRS corresponding to the same SL-PRS ID.

[0318] The length / end of the periodic SL-PRS detection window may also be related to priority.

[0319] The detection window size is equal to or greater than the maximum SL-PRS periodicity / repetition time gap or the LCM (least common multiple) of multiple SL-PRS periodicity / repetition time gaps.

[0320] For any periodically transmitted SL-PRS resource, there is a detection window to determine if that particular one is available, therefore a selection window may not be necessary.

[0321] The selection window includes some SL-PRS resources configured for the UE.

[0322] The size of the selection window can be n*T, where T is the SL-PRS periodicity or the time gap between two repeating instances of a SL-PRS corresponding to the same SL-PRS ID.

[0323] If the UE discovers / decodes within a time range / window that multiple configured resources are unavailable or conflict with SL-PRS resources of other UEs, the UE may need to switch SL-PRS configurations.

[0324] Scenario 2: Resource allocation in scheme 2 considers both periodic SL-PRS and SL data.

[0325] For the same SL-PRS selection window, the detection window size for non-SCI SL-PRS can be different from the detection window size for SL data, as shown in FIG.

[0326] Detection Window

[0327] Time domain:

[0328] max{SL-PRS detection window size, SL data detection window size}

[0329] Or, the union of the SL-PRS detection window and the SL data detection window.

[0330] Frequency domain:

[0331] Consider the location of frequency resources of both the SL Data Pool and the SL-PRS

[0332] The selection window in this scenario can be either the selection window for periodic SL-PRS as described in scenario 1 or the selection window for SL data.

[0333] Scenario 3: Scheme 2 resource allocation: When both periodic SL-PRS and SPCI reservation SL-PRS are supported, as shown in Figure 21. Consider possible conflicts between periodic SL-PRS and SPCI reservation SL-PRS.

[0334] Detection Window

[0335] Time domain:

[0336] max{Periodic SL-PRS detection window size, SPCI detection window size}

[0337] Or, the union of the periodic SL-PRS detection window size and the SPCI detection window size

[0338] Frequency domain:

[0339] Consider the location of frequency resources for the SL data pool, SPCI reserved SL-PRS and periodic SL-PRS

[0340] The selection window in this scenario can be either the selection window for periodic SL-PRS as described in scenario 1, or the selection window for SPCI reserved SL-PRS as described in embodiment 6.

[0341] Scenario 4: Scheme 2 Resource Allocation: When both periodic SL-PRS and SPCI reserved SL-PRS are supported. As shown in Fig. 22, we consider the possible conflicts between periodic SL-PRS, SPCI reserved SL-PRS and SL data.

[0342] Detection Window

[0343] Time domain:

[0344] max{Periodic SL-PRS detection window size, SPCI detection window size, SL data detection window size}

[0345] Or, the union of the periodic SL-PRS detection window size, the SPCI detection window size and the SL data detection window size.

[0346] Frequency domain:

[0347] Consider the location of frequency resources for the SL data pool, SPCI reserved SL-PRS and periodic SL-PRS

[0348] The selection window in this scenario can be either the selection window for periodic SL-PRS as described in scenario 1, or the selection window for SL data, or the selection window for SPCI reserved SL-PRS as described in embodiment 6.

[0349] If a collision is detected by the UE, how to select?

[0350] SL data, SCI SL-PRS, has priority value indicated by SCI / SPCI

[0351] Periodic SL-PRS

[0352] Add priority related information to the sequence.

[0353] Decode a set of SL-PRS configurations including priority information based on the sequence ID configuration and / or resource transmission location information. When the UE obtains the sequence ID configuration information and / or the resource transmission location information of other UEs, the UE can decode the SL-PRS configurations including priority information.

[0354] The prioritization rules may be (pre)configured or specified, and if so, at least one of the following rules may be applied:

[0355] The periodic SL-PRS has higher priority than all other SL signals / data

[0356] Periodic SL-PRS has lower priority than all other SL signals / data

[0357] The periodic SL-PRS has higher priority than the PSSCH and the SCI / SPCI reserved SL-PRS, but lower priority than the PSCCH.

[0358] The periodic SL-PRS has a higher priority than the PSSCH, but a lower priority than the SCI / SPCI reserved SL-PRS, the PSCCH.

[0359] The periodic SL-PRS has higher priority than the PSCCH and the SCI / SPCI reserved SL-PRS, but lower priority than the PSSCH.

[0360] The periodic SL-PRS has higher priority than the PSCCH and PSSCH, but lower priority than the SCI / SPCI reserved SL-PRS.

[0361] The periodic SL-PRS has higher priority than the PSCCH, but lower priority than the PSCCH and the SCI / SPCI reserved SL-PRS.

[0362] SL-PRS sequence IDs need to be (pre)defined or (pre)configured based on whether they are odd or even

[0363] An odd sequence ID may correspond to a higher priority, or an even sequence ID may correspond to a higher priority.

[0364] VIII. Embodiment 7

[0365] Scheme 2 SL-PRS resource allocation

[0366] Unlike SL communications, different SL-PRS resources from either different or the same UEs may be multiplexed in a TDM or FDM manner.

[0367] In case of Scheme 2 UE autonomous selection of SL-PRS resources, whether the UE performs resource exclusion or not is not only related to SL-PRS RSRP measurements and Tx priority (for both UEs), but also to whether the detecting UE and a UE belonging to the detected SPCI are in the same positioning session and the two UEs have a positioning signaling dialogue or not.

[0368] How to select SL-PRS resources based on detection results?

[0369] Periodic SL-PRS

[0370] If, after detecting the decoding of the TDM:SL-PRS / sequence, the UE determines that the other UE is its destination UE and / or source UE or two UEs are in the same positioning session, UE-A needs to exclude the SL-PRS resources reserved by the other UE.

[0371] If, after detecting the decoding of the FDM:SL-PRS / sequence, the UE determines that the other UE is not its destination UE and / or source UE, or the two UEs are not in the same positioning session, then UE-A does not need to exclude resources reserved by the other UE. The SL-PRS resources from the two UEs can apply the FDM pattern.

[0372] As shown in FIG. 23, two UEs may have different comb offsets, and as long as the two UEs do not have positioning signaling interaction, UEs with different comb offsets can transmit SL-PRS resources in the same slot / time.

[0373] For SPCI reservation SL-PRS

[0374] If, after detecting the TDM:SPCI, the UE determines that the other UE is its destination UE and / or source UE, or the two UEs are in the same positioning session, UE-A needs to exclude the SL-PRS resources reserved by the other UE.

[0375] FDM: If after detecting SPCI, the UE determines that the other UE is not its destination UE and / or source UE, or the two UEs are not in the same positioning session, then UE-A does not need to exclude resources reserved by the other UE. The SL-PRS resources from the two UEs can apply the FDM pattern.

[0376] Different UEs may have different comb offsets.

[0377] 24 is an example flow chart for performing sidelink (SL) positioning. Operation 2402 includes transmitting, by the wireless device, a sidelink positioning reference signal (SL-PRS) over a SL-PRS resource, the SL-PRS resource being in a SL-PRS resource pool. Operation 2404 includes performing, by the wireless device, sidelink positioning. In some embodiments, the method may be performed according to embodiments 1, 2, 4, and 5. In some embodiments, performing further steps of the method may be based on better system performance than a legacy protocol.

[0378] In some embodiments, the method further includes performing, by the wireless device, joint sidelink and uu positioning. In some embodiments, the SL-PRS resource pool may be configured by a gNodeB (gNB) or a Location Management Function (LMF), or may be pre-configured and stored on the wireless device. In some embodiments, a configured SL-PRS resource pool has a higher priority than a pre-configured SL-PRS resource pool.

[0379] In some embodiments, the method further includes receiving, by the wireless device, a SL-PRS configuration, wherein one or more of the SL-PRS transmissions, the SL-PRS resources, the SL-PRS resource pool, and the SL-PRS configuration are configured with the priority values.

[0380] In some embodiments, whether the SL-PRS resource pool is configured or preconfigured is indicated by control information, hi some embodiments, the SL-PRS resource pool is configured or preconfigured with one or more of a SL-PRS resource pool configuration, a SL-PRS configuration, a SL-PRS control information, a synchronization reference, a Scheme 2 configuration, and a power control configuration.

[0381] In some embodiments, the SL-PRS resource pool occupies a resource pool that is different from one or more resource pools occupied by SL data communications, hi some embodiments, the SL-PRS resource pool is configured or pre-configured with a logical slot set to avoid time regions that overlap with SL data communications.

[0382] In some embodiments, the SL-PRS resource pool shares a resource pool with SL data communications. In some embodiments, the SL-PRS resource pool is configured to use a reserved portion of the resource pool's physical resource blocks (PRBs). In some embodiments, the SL-PRS resource pool is associated with another resource pool linked to the SL data communications based on a SL resource pool index indication or a SL resource pool group list indication. In some embodiments, one or more of the SL-PRS sequence identification, SL-PRS resource bandwidth, wireless device identification, comb size, and comb offset are the same for the resource pool and the other resource pool.

[0383] In some embodiments, the SL-PRS resource pool is configured or pre-configured with SL-PRS sequences derived based on a sequence generation formula or sequence configuration. In some embodiments, the SL-PRS sequence is associated with an identity of the wireless device. In some embodiments, the SL-PRS sequence is associated with an identity of the receiving wireless device or service type. In some embodiments, the SL-PRS sequence is associated with an offset value. In some embodiments, the SL-PRS sequence is associated with a SL-PRS configuration.

[0384] In some embodiments, the method further includes receiving, by the wireless device, control information, the control information associated with the SL-PRS resources. In some embodiments, the control information and the SL-PRS resources are contained in a physical sidelink control channel (PSCCH). In some embodiments, the control information triggers one or more SL-PRS opportunities or SL-PRS samples. In some embodiments, the control information includes a location and a priority of the SL-PRS resources. In some embodiments, the SL-PRS resources are divided into one or more frequency ranges, and the method further includes transmitting, by the wireless device, the control information on the one or more frequency ranges.

[0385] In some embodiments, the control information includes one or more of SL-PRS priority, SL-PRS frequency resource allocation, SL-PRS time resource allocation, next control information time allocation, next control information frequency allocation, SL-PRS resource reservation period, SL-PRS pattern, SL-PRS configuration, SL-PRS periodicity, SL-PRS resource slot offset, SL-PRS resource symbol offset, SL-PRS repetition, SL-PRS symbol number per slot, SL-PRS muting pattern, SL-PRS resource power, SL-PRS sequence identification, SL-PRS comb size, SL-PRS comb offset, wireless device identification, SL-PRS request, SL-PRS indication, indicator for presence of SL-PRS transmission, indication for absence of SL-PRS transmission, control information time limit, and control information validity time.

[0386] 25 is an example flowchart for receiving and transmitting sidelink (SL) related information. Operation 2502 includes receiving, by the network device, a sidelink (SL) related information request. Operation 2504 includes transmitting, by the network device, an SL related information report or an SL related information update in response to the SL related information request. In some embodiments, the method may be implemented according to embodiment 3. In some embodiments, performing further steps of the method may be based on better system performance than legacy protocols.

[0387] In some embodiments, receiving the SL related information request includes receiving a SL related information request from a location management function (LMF), and transmitting the SL related information report or the SL related information update includes transmitting the SL related information report or the SL related information update to the LMF. In some embodiments, the SL related information request includes one or more of a wireless device identification, a transmission / reception point (TRP) identification, a SL positioning reference signal (SL-PRS) configuration, a SL related information report type, and a response time.

[0388] In some embodiments, the SL related information report or SL related information update includes one or more of gNodeB (gNB) information, an SL data communications resource pool configuration including a logical slot set for an SL data communications resource pool, and an SL positioning reference signal (SL-PRS) resource pool configuration including a logical slot set for an SL-PRS resource pool. In some embodiments, the method further includes transmitting, by the network device, the SL positioning reference signal (SL-PRS) related configuration to the wireless device.

[0389] 26 is an example flow chart for detecting and selecting SL-PRS resources. Operation 2602 includes detecting, by the wireless device, a sidelink positioning reference signal (SL-PRS) configuration within a detection window. Operation 2604 includes selecting, by the wireless device, a SL-PRS resource within a selection window based on the detected SL-PRS configuration. In some embodiments, the method may be implemented according to embodiments 5, 6, and 7. In some embodiments, performing further steps of the method may be based on better system performance than legacy protocols.

[0390] In some embodiments, the SL-PRS configuration includes an SL-PRS sequence, and detecting the SL-PRS configuration includes decoding the SL-PRS sequence. In some embodiments, the method further includes detecting, by the wireless device, sidelink control information (SCI) for the SL data communication. In some embodiments, the size of the detection window is a maximum or a union of a size of the detection window for the SL-PRS configuration and a size of the detection window for the SL data communication.

[0391] In some embodiments, the size of the detection window is related to the SL-PRS periodicity or the SL-PRS repetition time interval. In some embodiments, the selected SL-PRS resource is associated with a SL-PRS Reference Signal Received Power (RSRP) measurement, a SL-PRS priority, and a positioning session of the wireless device.

[0392] In some embodiments, the method further includes detecting, by the wireless device, a SL-PRS configuration indicated by the control information. In some embodiments, a size of the detection window is equal to or greater than an interval between the control information and the neighbor control information. In some embodiments, selecting the SL-PRS resource includes avoiding a conflict between selecting a periodic SL-PRS configuration and a SL-PRS configuration indicated by the control information.

[0393] In some embodiments, the size of the detection window is the maximum or union of the size of the detection window of the periodic SL-PRS configuration and the size of the detection window for the SL-PRS configuration indicated by the control information. In some embodiments, the size of the detection window is the maximum or union of the size of the detection window for the periodic SL-PRS configuration, the size of the detection window for SL data communication, and the size of the detection window for the SL-PRS configuration indicated by the control information.

[0394] In some embodiments, selecting the SL-PRS resource includes selecting a periodic SL-PRS configuration, or a SL-PRS configuration indicated by the control information based on a priority value assigned to the periodic SL-PRS configuration, or a SL-PRS configuration indicated by the control information. In some embodiments, selecting the SL-PRS resource includes selecting a periodic SL-PRS configuration, or a SL-PRS configuration indicated by the control information based on a priority rule associated with the periodic SL-PRS configuration and the SL-PRS configuration indicated by the control information.

[0395] In some embodiments, the method further includes determining, by the wireless device, that another wireless device is in the same positioning session as the wireless device or has a positioning signaling interaction with the wireless device. In some embodiments, the method further includes excluding, by the wireless device, SL-PRS resources from being reserved or configured for use by the other wireless device.

[0396] In some embodiments, the method further includes determining, by the wireless device, that another wireless device is not in the same positioning session as the wireless device or does not have a positioning signaling interaction with the wireless device. In some embodiments, the method further includes indicating, by the wireless device, that SL-PRS resources are available to be applied with frequency division multiplexing (FDM) to be reserved or configured for use by the other wireless device.

[0397] In some embodiments, the method further includes determining, by the wireless device, that another wireless device has a different comb offset than the wireless device. In some embodiments, the method further includes transmitting, by the wireless device, the SL-PRS over the SL-PRS resource on the same time domain resource as the other wireless device.

[0398] Devices configured or operable to perform the above-described methods are within the scope and spirit of this patent document.

[0399] In some embodiments, the methods described above are embodied in the form of processor executable code and stored in a non-transitory computer readable storage medium that, when executed by a processor, causes the processor to perform the methods described in this patent document.

[0400] FIG. 27 illustrates an example block diagram of a hardware platform 2700 that may be part of a network device (e.g., a base station) or a communication device (e.g., a user equipment (UE)). The hardware platform 2700 includes at least one processor 2710 and a memory 2705 having instructions stored thereon. The instructions, when executed by the processor 2710, configure the hardware platform 2700 to perform the operations described in FIGS. 1-26 and in various embodiments described in this patent document. The transmitter 2715 transmits or transmits information or data to another device. For example, a network device transmitter can transmit a message to a user equipment. The receiver 2720 receives information or data transmitted or transmitted by another device. For example, a user equipment can receive a message from a network device. For example, a UE or a network device may be implemented using the hardware platform 2700 as described herein.

[0401] The above-mentioned implementations may be applied to wireless communication. Figure 28 illustrates an example of a wireless communication system (e.g., a 5G or NR cellular network) including a base station 2820 and one or more user equipments (UEs) 2811, 2812, and 2813. In some embodiments, the UE accesses a BS (e.g., a network) using a communication link to the network (sometimes referred to as an uplink direction, as shown by dashed arrows 2831, 2832, 2833), which then enables subsequent communication from the BS to the UE (e.g., shown in a network-to-UE direction, sometimes referred to as a downlink direction, as shown by arrows 2841, 2842, 2843). In some embodiments, the BS transmits information to the UE (sometimes referred to as a downlink direction, as shown by arrows 2841, 2842, 2843), which then enables subsequent communication from the UE to the BS (e.g., shown in a UE-to-BS direction, sometimes referred to as an uplink direction, as shown by dashed arrows 2831, 2832, 2833). A UE may be, for example, a smartphone, a tablet, a mobile computer, a machine-to-machine (M2M) device, an Internet of Things (IoT) device, etc. The UEs described herein may be communicatively coupled to a base station 2820 shown in Figure 28. The UEs may also communicate with other UEs for sidelink communications.

[0402] The term "exemplary" is used herein to mean "an example," and does not imply an ideal or preferred embodiment, unless specifically stated otherwise.

[0403] Some of the embodiments described herein are described in the general context of a method or process that may be implemented in one embodiment by a computer program product embodied in a computer-readable medium including computer-executable instructions, such as program code, executed by a computer in a network environment. The computer-readable medium may include removable and non-removable storage devices, including but not limited to read-only memory (ROM), random access memory (RAM), compact disks (CDs), digital versatile disks (DVDs), and the like. Thus, the computer-readable medium may include non-transitory storage media. Generally, program modules may include routines, programs, objects, components, data structures, and the like that perform particular tasks or implement particular abstract data types. Computer or processor executable instructions, associated data structures, and program modules represent examples of program code for executing steps of the methods disclosed herein. A particular sequence of such executable instructions or associated data structures represents examples of corresponding acts for implementing the functions described in such steps or processes.

[0404] Some of the disclosed embodiments can be implemented as devices or modules using hardware circuits, software, or a combination thereof. For example, hardware circuit implementations can include separate analog and / or digital components integrated, for example, as part of a printed circuit board. Alternatively or additionally, the disclosed components or modules can be implemented as application specific integrated circuits (ASICs) and / or field programmable gate array (FPGA) devices. Some implementations may additionally or alternatively include digital signal processors (DSPs), which are dedicated microprocessors with architectures optimized for the operational needs of digital signal processing associated with the disclosed functionality of the present application. Similarly, the various components or subcomponents within each module may be implemented in software, hardware, or firmware. Connections between modules and / or components within a module may be provided using any one of the connection methods and mediums known in the art, including, but not limited to, communication via the Internet, wired, or wireless networks using appropriate protocols.

[0405] While this document contains many details, these should not be construed as limitations on the scope of the claimed invention or the invention that may be claimed, but rather as descriptions of features specific to particular embodiments. Certain features described in this document in the context of separate embodiments may also be implemented in combination in a single embodiment. Conversely, various features described in the context of a single embodiment may also be implemented in multiple embodiments separately or in any suitable subcombination. Furthermore, although features may be described above as acting in a particular combination and initially claimed as such, one or more features from the claimed combination may, in some cases, be cut out of the combination, and the claimed combination may be directed to a subcombination or a variation of the subcombination. Similarly, although each operation is shown in the figures in a particular order, this should not be understood as requiring that such operations be performed in the particular order shown, or in the sequential order, or that all of the operations shown be performed, to achieve desirable results.

[0406] Only some implementations and examples have been described; other implementations, extensions and variations are possible based on what is described and illustrated in this disclosure.

Claims

1. 1. A method of wireless communication, comprising: Transmitting, by a wireless device, a sidelink positioning reference signal (SL-PRS) over a SL-PRS resource, the SL-PRS resource being within an SL-PRS resource pool; and performing, by the wireless device, sidelink positioning; A method comprising:

2. The method of claim 1 , further comprising performing joint side link and uu positioning by the wireless device.

3. The method of claim 1 or 2, wherein the SL-PRS resource pool can be configured by a gNodeB (gNB) or a Location Management Function (LMF), or can be pre-configured and stored by the wireless device.

4. The method according to any of claims 1 to 3, wherein a configured SL-PRS resource pool has a higher priority than a pre-configured SL-PRS resource pool.

5. The method of any one of claims 1 to 4, further comprising receiving, by the wireless device, an SL-PRS configuration, wherein one or more of the SL-PRS transmissions, the SL-PRS resources, the SL-PRS resource pool, and the SL-PRS configuration are configured with a priority value.

6. The method according to any of claims 1 to 5, wherein whether the SL-PRS resource pool is configured or pre-configured is indicated by control information.

7. The method according to any of claims 1 to 6, wherein the SL-PRS resource pool is configured or pre-configured with one or more of a SL-PRS resource pool configuration, a SL-PRS configuration, a SL-PRS control information, a synchronization reference, a scheme 2 configuration, and a power control configuration.

8. The method according to any of claims 1 to 7, wherein the SL-PRS resource pool occupies a resource pool that is different from one or more resource pools occupied by SL data communications.

9. The method of claim 8, wherein the SL-PRS resource pool is configured or pre-configured with a set of logical slots to avoid time regions overlapping with the SL data communications.

10. The method according to any one of claims 1 to 7, wherein the SL-PRS resource pool shares a resource pool with SL data communication.

11. The method of claim 10, wherein the SL-PRS resource pool is configured to use a reserved portion of the physical resource blocks (PRBs) of the resource pool.

12. The method according to any of claims 10 and 11, wherein the SL-PRS resource pool is associated with another resource pool linked to the SL data communication based on a SL resource pool index indication or a SL resource pool group list indication.

13. 13. The method of claim 12, wherein one or more of a SL-PRS sequence identity, a SL-PRS resource bandwidth, an identity of the wireless device, a comb size, and a comb offset are the same for the resource pool and other resource pools.

14. The method according to any of claims 1 to 13, wherein the SL-PRS resource pool is configured or pre-configured with SL-PRS sequences derived based on a sequence generation formula or sequence configuration.

15. The method of claim 14 , wherein the SL-PRS sequence is associated with an identity of the wireless device.

16. The method of any of claims 14 and 15, wherein the SL-PRS sequence is associated with an identity of a receiving wireless device or a service type.

17. The method according to any of claims 14 to 16, wherein the SL-PRS sequence is associated with an offset value.

18. The method according to any of claims 14 to 17, wherein the SL-PRS sequence is associated with a SL-PRS configuration.

19. The method of any of claims 1 to 18, further comprising receiving, by the wireless device, control information, the control information being associated with the SL-PRS resource.

20. 20. The method of claim 19, wherein the control information and the SL-PRS resources are contained in a Physical Sidelink Control Channel (PSCCH).

21. The method of any of claims 19 and 20, wherein the control information triggers one or more SL-PRS opportunities or samples.

22. The method of any of claims 19 to 21, wherein the SL-PRS resources are divided into one or more frequency ranges, and further comprising transmitting, by the wireless device, the control information on the one or more frequency ranges.

23. 23. The method of any of claims 19 to 22, wherein the control information comprises one or more of: SL-PRS priority, SL-PRS frequency resource allocation, SL-PRS time resource allocation, next control information time allocation, next control information frequency allocation, SL-PRS resource reservation period, SL-PRS pattern, SL-PRS configuration, SL-PRS periodicity, SL-PRS resource slot offset, SL-PRS resource symbol offset, SL-PRS repetition, SL-PRS symbol number per slot, SL-PRS muting pattern, SL-PRS resource power, SL-PRS sequence identity, SL-PRS comb size, SL-PRS comb offset, identity of the wireless device, SL-PRS request, SL-PRS indication, indicator for presence of SL-PRS transmission, indication for absence of SL-PRS transmission, time limit of the control information, and validity time of the control information.

24. 1. A method of wireless communication, comprising: receiving, by a network device, a request for sidelink (SL) related information; transmitting, by the network device, a SL-related information report or a SL-related information update in response to the SL-related information request; A method comprising:

25. 25. The method of claim 24, wherein receiving the SL-related information request includes receiving the SL-related information request from a Location Management Function (LMF), and transmitting the SL-related information report or the SL-related information update includes transmitting the SL-related information report or the SL-related information update to the LMF.

26. The method of any of claims 24 and 25, wherein the SL related information request includes one or more of a wireless device identification, a transmission / reception point (TRP) identification, a SL positioning reference signal (SL-PRS) configuration, a SL related information report type, and a response time.

27. The method of any of claims 24 to 26, wherein the SL related information report or the SL related information update includes one or more of gNodeB (gNB) information, an SL data communications resource pool configuration including a logical slot set for the SL data communications resource pool, and an SL positioning reference signal (SL-PRS) resource pool configuration including a logical slot set for the SL-PRS resource pool.

28. The method according to any of claims 24 to 27, further comprising transmitting, by said network device, a SL-PRS related configuration to a wireless device.

29. 1. A method of wireless communication, comprising: Detecting, by a wireless device, a sidelink positioning reference signal (SL-PRS) configuration within a detection window; selecting, by the wireless device, an SL-PRS resource within a selection window based on the detected SL-PRS configuration; A method comprising:

30. 30. The method of claim 29, wherein the SL-PRS configuration includes a SL-PRS sequence, and detecting the SL-PRS configuration includes decoding the SL-PRS sequence.

31. 31. The method of claim 29, further comprising detecting, by the wireless device, a sidelink control information (SCI) for SL data communication.

32. The method according to any of claims 29 to 31, wherein the size of the detection window is the maximum or union of a size of a detection window for the SL-PRS configuration and a size of a detection window for SL data communication.

33. The method according to any of claims 29 to 32, wherein the size of the detection window is related to the SL-PRS periodicity or the SL-PRS repetition time interval.

34. The method of any of claims 29 to 33, further comprising detecting, by the wireless device, a SL-PRS configuration indicated by control information.

35. A method according to any of claims 29 to 34, wherein the size of the sensing window is equal to or greater than the interval between control information and neighbouring control information.

36. A method according to any of claims 29 to 35, wherein selecting the SL-PRS resource includes avoiding conflicts between selecting a periodic SL-PRS configuration and an SL-PRS configuration indicated by control information.

37. A method according to any of claims 29 to 36, wherein the size of the detection window is the maximum or union of the size of the detection window for a periodic SL-PRS configuration and the size of the detection window for an SL-PRS configuration indicated by control information.

38. A method according to any of claims 29 to 37, wherein the size of the detection window is the maximum or union of the size of the detection window for a periodic SL-PRS configuration, the size of the detection window for SL data communication, and the size of the detection window for an SL-PRS configuration indicated by control information.

39. The method according to any of claims 29 to 38, wherein the selected SL-PRS resource is associated with a SL-PRS reference signal received power (RSRP) measurement, a SL-PRS priority, and a positioning signaling interaction of the wireless device.

40. A method according to any one of claims 29 to 39, wherein selecting the SL-PRS resource comprises selecting the periodic SL-PRS configuration or the SL-PRS configuration indicated by the control information based on priority values ​​assigned to the periodic SL-PRS configuration and the SL-PRS configuration indicated by the control information.

41. A method according to any one of claims 29 to 40, wherein selecting the SL-PRS resource includes selecting the periodic SL-PRS configuration or the SL-PRS configuration indicated by the control information based on a priority rule associated with the periodic SL-PRS configuration and the SL-PRS configuration indicated by the control information.

42. determining, by the wireless device, that another wireless device is in the same location session as the wireless device or has a location signaling interaction with the wireless device; excluding, by the wireless device, the SL-PRS resources from being reserved or configured for use by other wireless devices; The method of any one of claims 29 to 41, further comprising:

43. determining, by the wireless device, that another wireless device is not in the same location session as the wireless device or does not have a location signaling interaction with the wireless device; indicating, by the wireless device, that the SL-PRS resources are available to be applied using frequency division multiplexing (FDM) to be reserved or configured for use by other wireless devices; The method of any of claims 29 to 42, further comprising:

44. determining, by the wireless device, that another wireless device has a different comb offset than the wireless device; transmitting, by the wireless device, a SL-PRS over the SL-PRS resource on the same time domain resource as other wireless devices; The method of any of claims 29 to 43, further comprising:

45. An apparatus for wireless communication comprising a processor, said processor configured to perform a method according to any of claims 1 to 44.

46. A computer readable program storage medium having stored thereon code which, when executed by a processor, causes the processor to perform a method according to any of claims 1 to 44.

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