Sidelink positioning reference signal

Abstract

A system, method, and device for transmitting and receiving sidelink positioning reference signals (SL-PRS) are provided. In one example, the user equipment (UE) includes memory and a baseband processor. The baseband processor is configured to cause the UE to select a sidelink positioning reference signal (SL-PRS) resource from a configured or pre-configured dedicated resource pool when executing instructions stored in memory. The dedicated resource pool includes candidate physical sidelink control channel (PSCCH) resources configured to carry single-stage sidelink control information (SCI) and candidate SL-PRS resources, but does not include candidate resources for physical sidelink shared channel (PSSCH) transmission. The baseband processor is configured to cause the UE to transmit SL-PRS on the selected SL-PRS resource.

Description

Background Art

[0001] The present invention relates generally to wireless communications, and more specifically to techniques for performing sidelink or device-to-device communications in a wireless network.

[0002] Some examples of circuits, devices, and / or methods are described below by way of example only. In this context, reference is made to the accompanying drawings. Brief Description of the Drawings

[0003] [Figure 1] Fig. 1 is a diagram of an example downlink (DL) positioning reference signal (PRS) in accordance with various aspects described herein.

[0004] [Figure 2] Fig. 2 is a diagram of an example sidelink shared resource pool in accordance with various aspects described herein.

[0005] [Figure 3] Fig. 3 is a diagram illustrating an example slot configuration for a physical sidelink control channel / physical sidelink shared channel (PSCCH / PSSCH) sidelink slot in accordance with various aspects described herein.

[0006] [Figure 4] Fig. 4 is a diagram illustrating sidelink communication operating in mode 1 or mode 2 in accordance with various aspects described herein.

[0007] [Figure 5] Fig. 5 is a diagram illustrating an example sidelink shared resource pool in accordance with various aspects described herein.

[0008] [Figure 6] Fig. 6 is a diagram illustrating an example sidelink dedicated resource pool in accordance with various aspects described herein.

[0009] [Figure 7A] This figure shows exemplary SL-PRS resources and different SL-PRS resource indexing and ordering rules in various embodiments described. [Figure 7B] This figure shows exemplary SL-PRS resources and different SL-PRS resource indexing and ordering rules in various embodiments described.

[0010] [Figure 8] This table shows the values ​​of k' used in SL-PRS sequence mapping according to the various described embodiments.

[0011] [Figure 9A] These are different exemplary mappings between PSCCH resources and Sidelink Positioning Reference Signal (SL-PRs) resources, described in various ways. [Figure 9B] These are different exemplary mappings between PSCCH resources and Sidelink Positioning Reference Signal (SL-PRs) resources, described in various ways. [Figure 9C] These are different exemplary mappings between PSCCH resources and Sidelink Positioning Reference Signal (SL-PRs) resources, described in various ways. [Figure 9D] These are different exemplary mappings between PSCCH resources and Sidelink Positioning Reference Signal (SL-PRs) resources, described in various ways.

[0012] [Figure 10] This flowchart outlines exemplary methods for transmitting SL-PRS in the various forms described.

[0013] [Figure 11] This is a message flow diagram outlining the SL-PRS transmission process in various disclosed forms.

[0014] [Figure 12]1 is a flow diagram outlining an example method for transmitting an SL-PRS using resources from a dedicated resource pool, in accordance with various aspects described.

[0015] [Figure 13] is a flow diagram outlining an example method for transmitting an SL-PRS based on an allocation from a network, in accordance with various aspects described.

[0016] [Figure 14] is a flow diagram outlining an example method for configuring transmission of an SL-PRS using resources from a shared dedicated resource pool linked to a dedicated resource pool, in accordance with various aspects described.

[0017] [Figure 15] is a flow diagram outlining an example method for requesting an SL-PRS from a UE for which a unicast link has not been established, in accordance with various aspects described.

[0018] [Figure 16] is a flow diagram outlining an example method for transmitting an SL-PRS based on configuration from an upper layer, in accordance with various aspects described.

[0019] [Figure 17] is a flow diagram outlining an example method for determining SL-PRS transmission power based on sidelink path loss, in accordance with various aspects described.

[0020] [Figure 18] is a flow diagram outlining an example method for transmitting an indication of an SL-PRS transmission time, in accordance with various aspects described.

[0021] [Figure 19] is a functional block diagram of a wireless communication network, in accordance with various aspects described.

[0022] [Figure 20] Simplified block diagrams of user equipment devices in various configurations described are shown. [Modes for carrying out the invention]

[0023] This disclosure is described with reference to the accompanying drawings. The drawings are not drawn to scale and are provided solely for illustrative purposes. Several aspects of this disclosure are described below with reference to illustrative uses. Many specific details, relationships, and methods are described to facilitate understanding of this disclosure. This disclosure is not limited to the illustrated order of operations or events, as some operations may occur in different orders and / or concurrently with other operations or events. Furthermore, not all illustrated operations or events are necessary to implement selected methodologies of this disclosure.

[0024] In many cases, mobile communication devices, such as user equipment (UEs), perform actions based on the device's location. Obvious examples include navigation applications and internet searches that seek results based on proximity to the device. To help UEs determine their location, base stations and access points transmit positioning reference signals (PRS) that can be received and measured by the UE for use in determining the UE's location. At the uplink (UL), the UE transmits sounding reference signals (SRS) that can be received and measured by the base station or access point. The base station or access point may transmit SRS measurements to the UE, or calculate and transmit positioning assistance information based on SRS measurements.

[0025] SRS and PRS are specifically designed to provide high levels of accuracy, coverage, and interference avoidance and suppression. Individual SRS / PRS are small in terms of time and frequency resources (occupying a single subcarrier and a single symbol) and can be distributed across the entire communication bandwidth using repetitions in multiple symbols so that SRS / PRS can be aggregated to store power. Figure 1 shows an exemplary PRS pattern 100 in which PRSs from two base stations are multiplexed over the slot duration of 12 symbols across the entire physical resource block (PRB). The distribution of PRS consists of a comb size that defines the number N of symbols that can be combined to cover all subcarriers in the frequency domain, and a comb offset that determines the location of the comb pattern. PRS pattern 100 has a comb size of 6, and the PRSs from two different base stations have different comb offsets to prevent them from overlapping. SRS follows a similar comb-based configuration.

[0026] Various positioning methods, including angle of arrival (AOA), angle of departure (AOD), time difference of observation (OTDOA), and round-trip time (RTT), are supported in 5G. All of these methods rely on measurements of PRS / SRS or other positioning reference signals. Details of these methods are omitted herein for brevity.

[0027] Vehicle-to-Everything (V2X) communication, which supports functions such as platooning and pedestrian avoidance, relies on precise and accurate location information of devices, which may be moving at high speeds in congested spaces and may be outside the coverage of cellular networks. To support V2X, it has been agreed that positioning methods should be developed that do not rely solely on signaling between the UE and the base station. This specification discloses techniques for supporting absolute or relative UE positioning, at least in part, based on side-link PRS (SL-PRS). SL-PRS is a positioning signal transmitted between a transmitting (TX) UE and a receiving (RX) UE, rather than between the UE and a base station or access point.

[0028] Some parameters associated with sidelink communication may be disclosed herein as “(pre)configured.” In NR, it is possible that a UE performing sidelink communication may not be within network coverage. In these situations, there may be no network configuration of sidelink communication parameters. When no network configuration is performed, both UEs may apply “pre-configured” parameter values. Pre-configured parameter values ​​are “built into” or programmed into the UE when the UE is manufactured. This set of pre-configured parameter values ​​remains the same for the UE and is used by the UE when there is no network coverage (or no configured parameter values ​​from the network). Thus, when a parameter value or other quantity associated with sidelink communication is described as “(pre)configured,” it means that the parameter value may be a “pre-configured” value at times and a network “configured” value at other times. Side Link Overview SL Shared Resource Pool

[0029] A specific slot is (pre-configured) to carry SL transmissions. Therefore, available sidelink resources include slots allocated for sidelinks (time resources) and common resource blocks (RBs) (frequency resources) within the sidelink bandwidth portion (SL-BWP). A subset of available SL resources is (pre-configured) to be used by several UEs for their SL transmissions. This subset of available SL resources is called the “shared resource pool”.

[0030] An exemplary shared resource pool for sidelink transmission is shown in Figure 2. A common resource block within the shared resource pool is called a PRB. The shared resource pool 200 includes a continuous PRB and continuous or discontinuous slots (pre-configured) for SL transmission. The shared resource pool is defined within a configured SL-BWP, and therefore a single numerology is used within the resource pool. The shared resource pool repeats in the time domain according to the resource pool duration.

[0031] In the frequency domain, the shared resource pool is divided into a set number of L consecutive subchannels, each subchannel containing a group of consecutive PRBs within a slot. The number of PRBs within a subchannel is M. sub This corresponds to the subchannel size configured (pre-configured) within the shared resource pool. A subchannel represents the smallest unit for sidelink data transmission or reception. In each slot of the shared resource pool, a subset of consecutive symbols is (pre-configured) for the SL. The number of symbols allocated to an SL can vary between 7 and 14 symbols. A shared resource pool (SRP) can be shared by several UEs for their SL transmissions. SRPs can be used for unicast, groupcast, and broadcast transmissions. A UE can consist of multiple SRPs for transmission (transmit SRPs) and multiple SRPs for reception (receive SRPs). SL physical channel

[0032] Sidelink communication takes place over four channels: the Physical Sidelink Control Channel (PSCCH), the Physical Sidelink Shared Channel (PSSCH), the Physical Sidelink Broadcast Channel (PSBCH), and the Physical Sidelink Feedback Channel (PSFCH). The PSBCH is primarily used for synchronization purposes, while the PSFCH is used to carry Hybrid Automatic Retransmission Request (HARQ) feedback. The PSCCH and PSSCH are used to transmit sidelink data.

[0033] Sidelink data is organized into transport blocks (TBs), and each TB is associated with sidelink control information (SCI). The SCI indicates the resources used by the PSSCH carrying the associated TB, as well as further information used to decode the TB. Throughout Release 17, PSCCHs are always transmitted in the same slot as the associated PSSCH. The SCI is transmitted in two stages: a first stage carried in the PSCCH and a second stage carried in the associated PSSCH. Dividing the SCI into two stages allows a non-RX UE of the transmitted TB to decode only the SCI of the first stage for channel sensing / resource selection purposes, as will be explained in more detail later.

[0034] The first-stage SCI indicates the PSSCH subchannel carrying the (re)transmission of the TB, as well as resource reservations for up to two further retransmissions of the TB. The first-stage SCI also indicates the resource reservation period in the case of semi-persistent resource reservations, the priority of the associated TB / PSSCH, and the format and size of the second-stage SCI. The second-stage SCI indicates the PHY layer source identifier (ID) of the TX UE and the PHY layer destination ID of the RX UE, as well as additional information used for decoding. SL slot structure

[0035] An exemplary slot structure 300 is shown in Figure 3. PSCCHs are multiplexed within resources that do not overlap with related PSSCHs in the same slot. A PSCCH is transmitted from the second SL symbol in the slot and starts from the lowest PRB in the subchannel(s) occupied by the related PSSCH. The number of symbols in a PSCCH is (pre-)set by the shared resource pool and can be 2 or 3 symbols. The size of the SCI in the first stage is fixed within the shared resource pool. Using L subchannels in the resource pool, there are L possible locations for a PSCCH in the slot, starting from the second SL symbol in the slot and from the lowest PRB in each subchannel. This limits the PRBs that must be blind-decoded for a PSCCH. All PSCCH symbols include a PSCCH demodulation reference signal (DMRS).

[0036] In some embodiments, the PSSCH carries the second-stage SCI and SL data payload. In addition to the source ID and destination ID, the second-stage SCI also includes a new data indicator and indications of the HARQ process ID, redundant version, whether HARQ feedback is enabled, and an optional geographic zone ID. The second-stage SCI is decoded using the PSSCH DMRS. The PSSCH can be transmitted from the second-to-last SL symbol in a slot. In contrast to the PSCCH which is transmitted in a selected consecutive PRB, the PSSCH may be transmitted in any subchannel of the SL-BWP. SL Resource Selection

[0037] Referring to Figure 4, sidelink communication can be performed according to one of two modes. In Mode 1, the network controls resource allocation and receives feedback (e.g., by signals transmitted or received by the base station or network node 400) about transport blocks (TBs) transmitted between TX UE401 and RX UE402. In some examples, resources for sidelink transmission are signaled to TX UE401 as a transmit grant, such as a dynamic grant or a configured grant. TX UE401 transmits the SCI and TB using the resources allocated by the network and, when feedback is enabled, receives a Hybrid Auto Retransmission Request Acknowledgment / Nack (HARQ-ACK / NACK) from RX UE402 over the PSFCH. TX UE401 reports the HARQ-ACK / NACK to the base station, and the feedback is used by the network to determine whether the TB has been decoded by RX UE402. If the network determines that the TB was not decrypted by RX UE402, the network sends a retransmission grant to TX UE401 indicating the resources to be used to retransmit the TB.

[0038] In Mode 2, the UE is (pre-configured) with a pool of sidelink resources, and TX UE401 autonomously selects resources from the sidelink resource pool to send TB to RX UE402 without requiring specific allocation from the network. Mode 2 is suitable for SL communication between closely spaced UEs, and / or when one or more of the UEs are outside of network coverage.

[0039] In Mode 2, the TX UE uses a sensing-based resource selection scheme to autonomously select resources for transmitting PSCCH / PSSCH. The TX UE starts from a shared resource pool received from the network or uses a (pre-configured) shared resource pool. During the sensing window, the TX UE decodes SCIs transmitted by other UEs. During the (pre-configured) resource selection window, the TX UE excludes candidate resources reserved by other UEs. The TX UE then senses the remaining PSCCH resources in the shared resource pool and measures the Reference Signal Received Power (RSRP) of the PSCCH or PSSCH. RSRP measurements may be performed on the DMRS carried by the PSCCH symbol. If the average RSRP for a candidate resource exceeds a (pre-configured) threshold, the TX UE excludes the candidate resource from the shared resource pool. After this exclusion, the TX UE checks whether the amount of remaining available candidate resources exceeds a (pre-configured) percentage (e.g., 20%) of all candidate resources in the resource selection window. If there are not enough remaining resources, the TX UE increases the threshold by the (pre-configured) step size and detects a PSCCH again during the selection window. If there are enough candidate resources remaining in the resource pool, the TX UE randomly selects a resource to send. The TX UE sends an SCI to reserve the selected resource so that it is excluded from candidate resources in the shared resource pool for future resource selections by the TX UE or other UEs.

[0040] During the preemption time interval before sending using the selected resource, the TX UE performs a preemption check based on SCIs sent by other UEs that reserve the resource. If the resource selected by the UE is reserved for sending a higher-priority PSSCH, the TX UE refrains from sending a PSCCH / PSSCH on the selected resource and restarts the resource selection process. SL Power Control

[0041] Power control for SL transmission of PSCCH, PSSCH, PSFCH, and PSBCH is open-loop. The transmit power of PSCCH is based on the transmit power derived for the associated PSSCH. Broadcast and groupcast PSSCH transmit power is determined based on DL path loss (between the TX UE and the base station). DL path loss can be derived by the TX UE based on measurements of a reference signal transmitted by the base station.

[0042] The unicast PSSCH transmit power can be configured (pre-configured) to be based on downlink (DL) path loss only, SL path loss only, or both DL and SL path losses. To determine the SL path loss, the TX UE receives an average or filtered RSRP value for the PSSCH DMRS of the TX UE from the RX UE via sidelink RRC or PC5 RRC signaling, based on several measurements. The TX UE uses this average RSRP value, along with the measured PSSCH transmit power, to determine the SL path loss. SL-PRS for SL positioning

[0043] Some of the unique characteristics of sidelink communication present challenges in SL-PRS design. For example, when a UE does not have SL data to send to the RX UE, the UE may be requested to send SL-PRS to the RX UE, meaning that an existing sidelink slot structure containing PSCCH and PSSCH in all slots may not be reused for SL-PRS transmission. A dedicated resource pool tuned for PSCCH and SL-PRS transmission may be preferable to reusing a shared resource pool that supports PSCCH / PSSCH transmission, but a dedicated resource pool presents additional design issues, as disclosed below. Other SL-PRS considerations include mode 1 / mode 2 resource allocation, power control, and timing considerations for SL-PRS. This specification discloses SL-PRS solutions that address many of these issues.

[0044] SL-PRS is defined for and contained within a single SL bandwidth portion (BWP) within a carrier. However, future implementations may support SL-PRS resource sets spanning multiple SL BWPs. SL-PRS is transmitted in time-frequency resources within a slot (pre-configured) for SL transmission. The configuration of an SL-PRS resource within a slot includes an SL-PRS resource ID, which is the time-domain indicator of the SL slot; the SL-PRS comb offset and comb size (N); the SL-PRS start symbol and number of symbols (M); and the SL-PRS frequency-domain allocation within the SL slot. In a shared resource pool, an SL-PRS frequency resource is identified by a combination of the SL-PRS resource ID and the SL-PRS frequency-domain allocation. In a dedicated resource pool, an SL-PRS resource is identified by an SL-PRS resource index that points to a combination of time resources (e.g., symbols) and frequency resources (e.g., resource elements) within the configured SL-PRS slot. Shared SL-PRS resource pool and dedicated SL-PRS resource pool

[0045] Figures 5 and 6 show examples of a shared resource pool (hereinafter referred to as SL-PRS SRP) 500 and a dedicated resource pool 600 (hereinafter referred to as SL-PRS DRP), respectively, which may be used for side-link positioning. A diagram legend for various SL signal types in the resource pools is provided below in Figures 5 and 6. Either or both of the SL-PRS-SRP(s) and SL-PRS-DRP(s) may be configured (pre-configured) for side-link positioning.

[0046] The SL-PRS SRP500 includes resources for PSCCH and PSSCH within the same slot. The SL-PRS SRP is divided into subchannels that can be used by different unicast pairs, groupcasts, or for broadcast. Note that, generally, the PSCCH resource can occupy the entire SL subchannel and, based on the (pre)configuration, can occupy two or three consecutive symbols. The SCI of the first stage (carried by PSCCH) and the SCI of the second stage (carried by PSSCH) can be used to indicate the SL-PRS. For SL-PRS comb sizes 1, 2, and 4 (see Figure 1 for examples of comb patterns), the SL-PRS is time-domain multiplexed with the PSCCH (e.g., occurring in different symbols) and has a frequency bandwidth spanning subchannels, as shown in Figure 5. A PSCCH in the top subchannel schedules SL-PRS spanning the top subchannel, and a PSCCH in the bottom subchannel schedules SL-PRS spanning the bottom subchannel. The SL-PRS is carried within several consecutive symbols within a slot. Priority may be assigned to the SL-PRS and indicated in the associated SCI.

[0047] In contrast, the SL-PRS-DRP 600 does not include resources for the PSSCH. The PSCCH subchannel is configured to carry a single-stage SCI that periodically or aperiodically displays one or more SL-PRS resources in a slot or multiple slots, as will be described in more detail later. The frequency resources that the SL-PRS spans include the entire bandwidth of the SL-PRS-DRP, rather than a single subchannel as in the case of the SL-PRS-SRS in Figure 5.

[0048] The PRB within resource pool 600 is divided into multiple subchannels, each subchannel of which may be used by a different TX UE. Figure 6 shows three different SCI sections, each carried by a subchannel of the PSCCH. Each SCI section may carry a single-stage SCI for a specific SL-PRS resource. The single-stage SCI indicates the source ID and destination ID (e.g., a unicast pair), the resource reservation period, the SL-PRS priority, and the cast type for the SL-PRS. The SCI in any section may indicate an SL-PRS resource in any of the SL-PRS symbols, per resource element, across the entire bandwidth of the resource pool. Thus, different SCIs can multiplex SL-PRS resources in the same symbol and PRB, enabling multiplexing of SL-PRS from several TX UEs, as shown for multiple base stations and DL PRS in Figure 1. Resource instructions in a dedicated resource pool

[0049] PSCCH resources can be assigned index values ​​based on the number of different subchannels carrying the SCI (e.g., 3, as in Figure 6). The order of PSCCH indexing can be based on frequency; for example, the lowest frequency subchannel can be assigned the lowest PSCCH index value.

[0050] Figures 7A and 7B illustrate different rules for assigning SL-PRS resource index values ​​to SL-PRS resources. In Figures 7A and 7B, as indicated by different shading, there are up to four different sets of configured SL-PRS resources, each set consisting of a comb size (N) and a different offset. A dedicated resource pool may contain several SL-PRS blocks or sessions within the same slot, each having M consecutive symbols that carry SL-PRS, with each SL-PRS block preceded by an automatic gain control (AGC) symbol. SL-PRS block 710 has a length M of 4 symbols and a comb size of 4. SL-PRS block 720 has a length of 2 symbols and a comb size of 4. SL-PRS block 730 has a length of 1 symbol and a comb size of 2.

[0051] Figure 7A shows SL-PRS resource indexing based firstly on the frequency of the SL-PRS resource and secondly on the SL-PRS resource itself. If the bandwidth of the SL-PRS is smaller than the bandwidth of the dedicated resource pool, the SL-PRS resource may be frequency-division multiplexed, and the SL-PRS resource index may be ordered by frequency. Frequency ordering may start from the "highest" frequency of the SL-DRP or from the "lowest" frequency of the SL-DRP, as shown in Figure 7A.

[0052] Figure 7B shows SL-PRS resource indexing based, firstly, the symbol in the SL-PRS resource, secondly, the frequency in the SL-PRS resource, and thirdly, the SL-PRS resource itself. If the bandwidth of the SL-PRS is smaller than the bandwidth of the dedicated resource pool, the SL-PRS resources may be frequency-division multiplexed, and the SL-PRS resource index may be ordered by frequency. Another SL-PRS resource indexing scheme indexes the SL-PRS resources by, firstly, the symbol in the SL-PRS resource, secondly, the SL-PRS resource itself, and thirdly, the frequency in the SL-PRS resource. The index labels in Figure B are also applied in this indexing order. Side link control information for SL-PRS

[0053] In addition to indicating the selected SL-PRS resource, in some examples, when necessary, the single-stage SCI also indicates the source ID and destination ID that identify the TX UE / RX UE unicast pair. The source ID and / or destination ID may be indicated by the full 24-bit MAC layer ID, the least significant bit (LSB) of any number of the 24-bit MAC IDs (e.g., 16 bits), or other bits based on the source ID / destination ID. The SCI may include bits encoding the SL-PRS priority. Three bits may indicate up to eight different priority levels. The SCI may include bits encoding the cast type. Two bits may be used to indicate one of broadcast, group cast, or unicast, or a single bit may be used to indicate either unicast or group cast / broadcast.

[0054] To indicate a periodic SL-PRS resource that occurs periodically within an SL slot during a certain period, the SCI may include b bits (e.g., 4) to indicate a resource reservation period identifier (ID). The resource reservation period ID is 2 b This indicates one of several different resource reservation periods. The resource reservation period mapped to the resource reservation period ID may be (pre-configured) for each dedicated resource pool.

[0055] To indicate an aperiodic SL-PRS resource or an SL-PRS retransmission resource, the SCI may include bits encoding the subchannel index of the first transmission of the SL-PRS. Depending on the configuration of the maximum number of SLs per reservation (e.g., sl-MaxNumPerReserve), the SCI may also encode the subchannel index of the first retransmission of the SL-PRS, and when the maximum number of resources per reservation is 3, it may encode the subchannel index of the second retransmission of the SL-PRS. When there are two or more SL-PRS mapped to each PSCCH, in the case of an aperiodic SL-PRS resource or an SL-PRS retransmission resource, the SCI may also include bits encoding the SL-PRS resource index of the first transmission of the SL-PRS. Depending on the configuration of the maximum number of SLs per reservation, the SCI may also encode the SL-PRS resource index of the first retransmission of the SL-PRS, and when the maximum number of resources per reservation is 3, it may encode the SL-PRS resource index of the second retransmission of the SL-PRS.

[0056] SCI can also be used by RX UE to transmit Layer 1 RSRP reports (e.g., raw RSRP measurements) or Layer 3 RSRP reports (e.g., filtered RSRP values).

[0057] The SL-PRS sequence can be mapped to a sequence starting with n(0) resource elements (k(time), l(frequency)) in slots on different antenna ports than the one assigned to the PSSCH. The mapping follows the following relationship, where α is the signal assigned to each resource element and β is the power control factor.

number

number

number

number

number

number

[0058] The reference point for k=0 can be (pre-configured) by the resource pool as the location of point A, which is the common reference point of the SL-BWP. Otherwise, the reference point can be subcarrier 0 within the common resource block 0. In other examples, the reference point is the lowest subcarrier in the resource pool or the lowest PRB of the SL-BWP, or the (pre-configured) or defined offset of the lowest subcarrier in the resource pool or the lowest PRB of the SL-BWP. Mapping from PSCCH to SL-PRS resources

[0059] To simplify signaling overhead, mapping between PSCCH resources and SL-PRS resources is possible. Figures 9A to 9D show several different types of mappings that can be configured (pre-configured) for each dedicated resource pool. As shown in Figures 9A and 9B, there can be one-to-one mappings between PSCCH indices and SL-PRS indices. Figure 9A shows a one-to-one mapping where the i-th PSCCH resource index (0 ≤ i ≤ X-1) is associated with the i-th SL-PRS resource in the slot. Figure 9B shows a one-to-one mapping where the i-th PSCCH resource index is mapped to a single SL-PRS resource, where the SL-PRS resource may not have the same index value as the PSCCH resource index. In the example in Figure 9B, the i-th PSCCH index is

number

number

[0060] As shown in Figures 9C and 9D, a one-to-many mapping can occur between a PSCCH index and an SL-PRS resource index. In this case, an additional parameter within the SCI indicates which of the (pre-configured) sets of SL-PRS resources mapped to the relevant PSCCH will carry the SL-PRS (e.g., using the SL-PRS resource index value). As shown in Figure 9C, each PSCCH index can be mapped to a contiguous set of SL-PRS resource indices. For example, the i-th PSCCH index may be mapped to an SL-PRS resource index value

number

number

[0061] In other examples, there is no predetermined mapping of PSCCH resources to SL-PRS resources, in which case the single-stage SCI will indicate one of the candidate SL-PRS resources in the slot selected for SL-PRS (for example, using the SL-PRS resource index value). SL-PRS transmission in Method 2

[0062] Figure 10 is a flowchart outlining an exemplary method 1000 that may be performed by a TX UE to transmit an SL-PRS when the TX UE is operating according to method 2, in which it selects from resources in a pre-configured resource pool rather than receiving an allocation from the network. Method 1000 includes, in 1010, receiving a (pre-configured) dedicated resource pool for use for SL positioning. An exemplary dedicated resource pool is shown in Figure 6. In 1020, in a manner similar to the legacy PSCCH / PSSCH candidate selection process outlined above with reference to mode 2 in Figure 4, the TX UE receives and measures the PSCCH / SCI for each slot in the dedicated resource pool. The TX UE may measure the RSRP of signals such as demodulated reference signals (DM-RS) associated with or included in the PSCCH.

[0063] In 1030, the UE selects a PSCCH resource using a process similar to the legacy PSCCH / PSSCH resource selection process outlined above, with reference to Mode 2 in Figure 4. When a detected SCI indicates a periodic SL-PRS resource, the TX UE assumes that the same SL-PRS resource is scheduled within a slot during each period of the resource reservation period. When there is a one-to-one mapping between PSCCH resources and SL-PRS resources, candidate resources can be defined with respect to subchannels for the PSCCH and slots. This is because the one-to-one mapping ensures that any conflicting PSCCHs within the same slot indicate the same SL-PRS resource. In this way, only subchannels (e.g., those assigned to the TX UE) need to be selected. This differs from legacy PSCCH / PSSCH candidate resource selection, where one or more subchannels may be selected.

[0064] When there is no mapping of PSCCH resources to SL-PRS resources, candidate resources may be defined with respect to individual SL-PRS resources and slots.

[0065] TX UE is a slot

number

number

number

[0066] In 1040, the UE selects an SL-PRS resource. If there is a mapping between the PSCCH resource and the SL-PRS resource, the TX UE selects the SL-PRS based on the mapping to the selected PSCCH resource. If there is no mapping between the PSCCH resource and the SL-PRS resource, the TX UE may select any SL-PRS resource in the slot. When the TX UE selects from two or more SL-PRS resources, the selection may be based on the SL-PRS priority, resource reservation periodicity, SL channel busy rate, and / or SL channel occupancy rate.

[0067] At 1050, the TX UE transmits a PSCCH containing an SCI among the selected candidate resources. As described above, an SCI may indicate an SL-PRS resource when there is no (pre-configured) one-to-one mapping between the PSCCH resource and the SL-PRS resource. At 1060, the TX UE transmits an SL-PRS among the selected SL-PRS resources.

[0068] The SL-PRS transmission method 1000 may also include a preemption check similar to the preemption check disclosed above with respect to the legacy PSCCH / PSSCH resource selection process. This preemption check may be an optional feature that can be enabled / disabled in a dedicated resource pool configuration. In a preemption time interval prior to the scheduled time for transmitting an SL-PRS, the TX UE detects an SCI and compares the priority of any other UE's scheduled SL-PRS that overlap with the SL-PRS transmitted by the TX UE with the priority of the SL-PRS transmitted by the TX UE. If an overlapping SL-PRS with a higher priority is scheduled, the TX UE performs a resource reselection.

[0069] For example, when there is a mapping between a PSCCH resource and an SL-PRS resource, the resources for preemption checking are the subchannel and the mapped SL-PRS. When there is no mapping between a PSCCH resource and an SL-PRS resource, the resources for preemption checking are all SL-PRS resources in the slot. Method 1: Resource allocation for SL-PRS

[0070] In Method 1, the network allocates resources to the TX UE for SL-PRS through resource allocation. Resource allocation can be downlink control information (DCI) or configured grants.

[0071] DCI Format 3_0 can be adapted for allocating resources for SL-PRS. The following fields in the existing DCI Format 3_0 are not required and can be repurposed: the "Lowest Index of Subchannel Allocation to Initial Transmit" field; the "SCI Format 1-A / Frequency Resource Allocation" field; the "PUCCH Resource Indicator" field; the "PSFCH-to-HARQ Feedback Timing Indicator" field; the "New Data Indicator" field; the "HARQ Process Number" field; and the "Counter Sidelink Allocation Index" field. The following fields can be retained from DCI Format 3_0: the "Resource Pool Index" field; the "Time Gap" field; the "SCI Format 1-A / Time Resource Allocation" field; and the "Configuration Index" field.

[0072] The following new fields not included in DCI format 3_0 may be added to DCI: the “Initial transmission subchannel index” field; the “First retransmission subchannel index” field; and the “Second retransmission subchannel index” field. Each of these fields is

number

number

number

[0073] When the adapted DCI format 3_0 is used for Method 1 SL-PRS resource allocation, the DCI may be scrambled according to the SL-PRS-DRP Random Network Temporary Identifier (RNTI) or the SL-PRS-Configured Scheduled (CS)DRP RNTI if the dedicated resource pool uses a different RNTI than the legacy sidelink RNTI. If the dedicated resource pool uses the same RNTI as the legacy sidelink, the DCI may be scrambled according to the SL-PRS-RNTI or the SL-PRS-CS-RNTI. Fields not required from the legacy DCI format 3_0 may be reserved or reinterpreted as new fields identified above. An alternative approach may provide a new DCI format 3_X that does not include fields not required for scheduling SL-PRS resources.

[0074] For shared resource pools, the following new fields not included in DCI format 3_0 may be added to the DCI: "Initial transmission SL-PRS resource index" field; "First retransmission SL-PRS resource index" field; "Second retransmission SL-PRS resource index" field. Each of these fields is:

number

number

[0075] When a configured grant is used to allocate resources for SL-PRS, a new IE (for example, called SL_PRS_ConfiguredGrantConfig) may be provided, which includes the following fields: sl-PRS-ConfigIndexCG and sl-PRS-PeriodCG. For Type 1 configured grants (which do not require DCI activation), the field rrc-ConfiguredSidelinkGrant is also included, which provides instructions for the following parameters: sl-PRS-TimeResourceCG-Type1, sl-PRS-SubchannelCG-InitialTx-Type1, sl-PRS-SubchannelCG-ReTx1-Type1, sl-PRS-SubchannelCG-ReTx2-Type1, sl-PRS-TimeOffsetCG-Type1, sl-PRS-TimeReferenceSFN-Type1, sl-PRS-ResourcePoolID, sl-PRS-ResourceIndexCG-InitialTx-Type1, sl-PRS-ResourceIndexCG-ReTx-Type1, and sl-PRS-ResourceIndexCG-ReTx2-Type1. Configuration information and source ID / destination ID in the dedicated resource pool

[0076] Compared to legacy SL communication, where a unicast link is established for the purpose of transmitting SL data, in SL positioning, a UE may request SL-PRS from a TX UE that does not currently have a unicast link. When a UE is configured with a dedicated resource pool for SL-PRS, there are no resources to exchange configuration and capability information. To address this problem, a shared resource pool may be linked to the dedicated resource pool in the configuration of the dedicated resource pool, or a default shared resource pool may be configured (pre-configured) for use when requesting SL-PRS. The link between the shared resource pool and the dedicated resource pool may be achieved by identifying the linked pool in the configuration of one or both of the linked pools. The UE uses the resources of this linked or default shared resource pool to establish a unicast link with the TX UE and exchange configuration and capability information, open-loop power configuration information (e.g., RSRP measured values ​​or filtered values), etc. Once the unicast link is established, different shared resource pools may be linked to the dedicated resource pool for future data transmissions between UEs.

[0077] Another challenge presented by the dedicated resource pool is the lack of a resource (e.g., PSSCH) to exchange the PHY layer source ID and destination ID within the SCI requesting the SL-PRS. Figure 11 is a message flow diagram outlining the process by which RX UE 1120 can request and receive an SL-PRS from TX UE 1110, which does not have a unicast link. At 1130, the RX UE determines the MAC destination ID for the TX UE and self-assigns the RX UE MAC layer source ID. At 1120, the UE may use one of several possible techniques to determine the TX UE MAC layer destination ID.

[0078] In one alternative, the RX UE establishes a unicast link 1140 with the TX UE using resources from the linked or default shared resource pool (as described above), providing the TX UE with the MAC layer source ID of the RX UE and determining the MAC layer destination ID of the TX UE. A one-to-one mapping may exist between shared resource pools, a particular shared resource pool may be linked to two or more dedicated resource pools, or a particular dedicated resource pool may be linked to two or more shared resource pools. The UE may use the same or different source IDs for dedicated and shared resource pools.

[0079] A configuration for a dedicated resource pool may identify the shared resource pool to which it is linked. A configuration for a shared resource pool may identify the dedicated resource pool to which it is linked. In other examples, the link between a dedicated resource pool and a shared resource pool is provided by a higher layer, for example, along with sequence generation parameters. A unique identifier for a dedicated or shared resource pool can be used to identify a specific resource pool within the configuration of a linked pool. This linked resource pool may be identified by a resource pool ID, a resource pool configuration (e.g., an SL-ResourcePool information element), or resource pool time and frequency resources.

[0080] Alternatively, the RX UE1120 determines the TX UE MAC layer destination ID based on the positioning application ID assigned to the TX UE1110 by the RX UE using the positioning application, or by (pre)configuration. In this approach, a default positioning application layer ID may be defined, and / or a user-defined positioning application layer ID may be created. When NR PC5 is selected, the sidelink policy / parameter provisioning provides a mapping of vehicle-to-everything (V2X) service types to the default mode of communication and / or positioning to support SL positioning. Furthermore, the mapping of V2X service types to MAC layer destination IDs is established for broadcast, groupcast, and initial signaling to establish a unicast link for communication and / or positioning.

[0081] In a third alternative, the MAC layer destination ID may be determined based on a dedicated resource pool configuration (pre-configured) on the RX UE or SIM card. In other examples, the MAC layer destination ID may be provided by signaling 1145 from a network device 1125 such as a V2X server, or by updates received from a policy control function (PCF).

[0082] At 1150, the RX UE determines the PHY layer TX UE destination ID and RX UE source ID based on the MAC layer destination ID and source ID determined at 1130. The PHY layer ID may correspond to a specific number of LSBs of the MAC layer ID. At 1160, RX UE 1120 sends an SCI to TX UE 1110 using the PHY layer destination ID to request an SL-PRS from the TX UE. The SCI may be sent in a shared resource pool or a dedicated resource pool, and an SL-PRS may be requested in a shared resource pool or a dedicated resource pool.

[0083] In some examples, the TX UE 1110 may select a resource in Method 1 or Method 2, as described above with respect to Figures 7-10, and transmit an SL-PRS in 1180. In other examples, as shown in Figure 11, the TX UE 1110 sends an intermediate request for an SL-PRS configuration 1170 to a higher layer positioning protocol 1115, such as Sidelink Positioning Protocol (SPP), New Radio Positioning Protocol (NRPPa), or Long-Term Evolution Positioning Protocol (LPP). The higher layer positioning protocol then transmits the SL-PRS configuration 1175 to the TX UE and RX UE, schedules the SL-PRS, and triggers the TX UE to transmit an SL-PRS 1180 to the RX UE. Open-loop power configuration in a dedicated resource pool

[0084] As disclosed above, the open-loop power configuration (OLPC) for PSCCH / PSSCH transmit power can be based on (DL) path loss only, SL path loss only, or both DL and SL path losses. Similarly, the OLPC for PSCCH and SL-PRS transmission in the dedicated resource pool can be based on DL path loss only, SL path loss only, or both DL and SL path losses. However, to determine the SL path loss, in legacy OLPC, the TX UE needs to receive an averaged or filtered RSRP value from the RX UE based on measurements made by the RX UE on the TX UE's PSCCH DMRS or other reference signal. The TX UE uses the filtered RSRP value along with the measured PSSCH transmit power to determine the SL path loss (SL path loss = filtered RSRP - PSSCH transmit power). The dedicated resource pool does not have a PSSCH resource to carry filtered RSRP values ​​or raw RSRP measurement data. Therefore, modifications to legacy OLPC should be made to support the use of the dedicated resource pool for SL-PRS.

[0085] In one example, when the UE is within coverage, only DL path loss is used to determine the PSCCH and SL-PRS transmit power. If the UE is not within coverage, OLPC is not supported, and the UE transmits PSCCH and SL-PRS at maximum power (Pc_max).

[0086] In another example, the shared resource pool may be linked to a dedicated resource pool as disclosed above with reference to Figure 11, or the default shared resource pool may be configured (pre-configured) for use in SL positioning. The TX UE can initiate a unicast link with the RX UE using the linked or default shared resource pool and receive RSRP feedback from the RX UE using the unicast link. The shared resource pool may include PSSCH resources that can be used to carry RSRP feedback, such as filtered RSRP values ​​on the Medium Access Control (MAC) control element (CE), or may include using a legacy SL communication method on the PSSCH. This feedback is used to determine the SL path loss for determining the PSCCH and SL-PRS transmit power.

[0087] In another example, the TX UE uses a single-stage SCI to receive PHY layer RSRP reports or RRC layer RSRP reports sent by the RX UE at the PHY layer.

[0088] In another example, the RX UE sends a PHY layer RSRP report to the RX UE. One option of this approach is for the RX UE to perform filtering or averaging of several RSRP measurements and feed back the resulting filtered RSRP value. Another option is for the RX UE to send the measurement results to the TX UE, and the TX UE's RRC layer performs filtering on the measurement results to calculate the filtered RSRP value. The measurement results may be sent in a single-stage SCI of a dedicated resource pool. Another option is for the RX UE to calculate the SL path loss. The SL path loss is determined based on the difference between the transmit power of a reference signal (e.g., PSCCH Tx power) reduced by the filtered RSRP value. In this approach, the RX UE may receive an indication of the transmit power of the reference signal sent by the TX UE. This indication of the reference signal transmit power may be included in a single-stage SCI of a dedicated resource pool sent to the RX UE. The RX UE can also use a single-stage SCI to communicate the calculated SL path loss or RSRP feedback (e.g., RSRP measurement or filtered RSRP value) to the TX UE. The bit width in the single-stage SCI for encoding the transmit power (when the SCI is sent by the TX UE) and the RSRP feedback (when the SCI is sent by the RX UE) can be fixed or configurable, and different granularity / resolution for the transmit power compared to the RSRP feedback is optionally supported.

[0089] In another example, the transmit power for a PSCCH is determined using a formula that determines the transmit power for a legacy PSCCH symbol where the corresponding PSCCH is not transmitted.

[0090] In another example, the SL-PRS transmit power in a symbol is equal to the total power of the PSCCH in the dedicated resource pool. Alternatively, the SL-PRS transmit power per resource element (RE) is equal to the transmit power of the PSCCH per RE, which is related to the following relationship:

number

number

number

number

number

number

number

number

number

[0091] Positioning information may be determined based on the difference between the SL-PRS reception time and the SL-PRS transmission time. The TX UE may report the actual SL-PRS transmission time to entities performing positioning-related calculations used for calculating the transmission time / reception or measurement time difference.

[0092] In some embodiments, to support SL-PRS transmission time communication, absolute time duration is signaled with respect to physical layer time units (Tc), which are fixed quantities defined by TS 38.211. Absolute time duration may be configured using RRC signaling and / or transmitted by positioning protocols from the Location Management Function (LMF). In SL-PRS transmission time reporting, the actual transmission time is expressed as the amount of total Tc within the absolute time duration. Absolute time duration may be defined as slots, subframes, or frames. Therefore, the granularity of absolute transmission time in transmission reporting is based on absolute time duration. The granularity of absolute transmission time may be configured (pre-configured) per resource, per resource pool, or per positioning.

[0093] The TX UE reports absolute transmission time as the amount of Tc(Tc(transmit)) within an absolute duration. The absolute transmission time report may report an actual Tc(transmit) or a quantized Tc(transmit) value, where the Tc quantization level can be configured to determine the number of bits used to signal the transmission time in the report. Tables 1 and 2 below show different examples of the number of bits that may be used to quantize absolute transmission time when the absolute time duration is a subframe (Table 1) or a slot (Table 2). Note that when a slot is the absolute time duration, the number of Tc per slot varies based on the subcarrier interval used, as does the number of bits required to encode Tc(transmit). Similar techniques may be used to signal SL-PRS reception or measurement time.

[0094] In some examples, absolute time spans subframe or slot boundaries. For instance, the absolute time duration across a subframe (1 ms) may range from -0.5 ms or -1966080 / 2Tc to 0.5 ms or 1966080 / 2Tc. [Table 1] Table 1 - Subframe [Table 2] Table 2 - Slots

[0095] When the transmission time occurs in one duration (e.g., a first slot, subframe, or frame) and the reception time occurs in another duration (e.g., a second slot, subframe, or frame), and therefore Tc (absolute transmission time) > Tc (absolute reception time), different compensation measures may be taken by the LMF or other entity receiving the transmission time or measurement / reception time for positioning calculations. In one example, the LMF may discard the measurement. In another example, the LMF may estimate the correct time difference by assuming that the reception time occurs in the immediately following duration (e.g., using modulo arithmetic). In yet another example, the LMF reconstructs the absolute time so that it is defined over an increased duration. In yet another example, an explicit signal is used to indicate whether the measurement is in the same duration period (e.g., the same subframe or slot). For example, a single bit may be set to 0 if the transmission and reception times are in the same duration period, and the bit may be set to 1 if the transmission and reception times are in subsequent duration periods. If three or more duration periods span between the transmit and receive times, more bits may be used to signal the number of duration periods that span both the transmit and receive times.

[0096] Absolute time can be defined based on the start of the orthogonal frequency division multiplexing (OFDM) symbol for SL-PRS transmission / measurement. For example, the information element nr-TimeStamp-RxTx may define a UE measurement / transmission-related timestamp. The IE may include the nr-SFDN field, which specifies the NR system frame number (SFN) for UEs within coverage or the NR direct frame number (DFN) for UEs outside coverage. The field nr-Slot can specify the NR slot number within the NR SFN or DFN indicated by the nr-SFDN field. The field nr-symbol can specify the NR OFDM symbol number within the slot indicated by the nr-Slot field. The field Tc_value can encode a timestamp with respect to Tc across symbols, slots, or subframes.

[0097] Figure 12 is a flowchart outlining an exemplary method 1200 for transmitting SL-PRS using a dedicated resource pool. Method 1200 may be performed by TX UE 401 and / or 1110 in Figures 4 and 11, respectively. The method includes, in 1210, selecting a sidelink positioning reference signal (SL-PRS) resource from a configured or pre-configured dedicated resource pool. The dedicated resource pool includes candidate physical sidelink control channel (PSCCH) resources configured to carry single-stage sidelink control information (SCI) and candidate SL-PRS resources, but the dedicated resource pool does not include candidate resources for physical sidelink shared channel (PSSCH) transmission. An exemplary dedicated resource pool is shown in Figure 6. The method includes, in 1220, transmitting SL-PRS on the selected SL-PRS resource.

[0098] In some embodiments, the method includes selecting periodic SL-PRS resources that occur within the same frequency domain resource in the same slot for each SL-PRS resource period during the reservation period. The method may also include selecting non-periodic SL-PRS resources.

[0099] Each candidate SL-PRS resource is identified by a slot index and a subchannel index, or by a slot index and an SL-PRS resource index. In some examples, as shown in Figures 7A and 7B, PSCCH resources in slots within a dedicated resource pool are indexed with respect to frequency location. As shown in Figure 7A, SL-PRS resources in slots within a dedicated resource pool may be indexed first by the frequency of the SL-PRS resource, and second by the SL-PRS resource itself. Alternatively, as shown in Figure 7B, SL-PRS resources in slots may be indexed first by the symbol within the SL-PRS resource, second by the frequency within the SL-PRS resource, and third by the SL-PRS resource, or first by the symbol within the SL-PRS resource, second by the SL-PRS resource, and third by the frequency.

[0100] As shown in Figures 9A to 9D, each PSCCH resource may be mapped to one SL-PRS resource, where the mapped SL-PRS resource index is the same as the PSCCH resource index, or the mapped SL-PRS resource index is different from the PSCCH resource index. Alternatively, each PSCCH may be mapped to a set of SL-PRS resources, and the method then includes sending an instruction for one selected from the set of SL-PRS resources in a single-stage SCI carried by the PSCCH resource. The set of SL-PRS resources has consecutive SL-PRS resource indices or interleaved SL-PRS resource indices. The method may include selecting an SL-PRS resource from the set of SL-PRS resources based on one or more of the priority, resource reservation periodicity, SL Channel busy rate, or SL Channel occupancy rate associated with the SL-PRS.

[0101] As shown in Figure 10, the method may include selecting SL-PRS resources from a dedicated resource pool by measuring the reference signal received power (RSRP) of a single-stage SCI in a candidate PSCCH of the dedicated resource pool, decoding the single-stage SCI to determine the resource reservation period and priority of the individual SL-PRS associated with the individual SCI, and excluding candidate resources associated with single-stage SCIs having an RSRP higher than a threshold from the candidate resource pool. The threshold is selected based on the priority indicated in the single-stage SCI or the priority of the SL-PRS.

[0102] The method may include decoding a single-stage SCI in a preemption time interval prior to the selected SL-PRS resource to determine whether the selected SL-PRS resource is reserved for a higher-priority SL-PRS, and refraining from transmitting an SL-PRS if the selected SL-PRS resource is reserved for a higher-priority SL-PRS. The method may include decoding a single-stage SCI in the same subchannel as the selected SL-PRS resource and comparing the priority of the SL-PRS associated with the single-stage SCI with the priority of the transmitted SL-PRS. The method may include decoding a single-stage SCI in all subchannels of the dedicated resource pool and comparing the priority of the individual SL-PRS associated with the single-stage SCI with the priority of the transmitted SL-PRS.

[0103] In some examples, a single-stage SCI includes one or more of the following indications: source ID for UE, destination ID for receiving (RX) UE, associated SL-PRS priority, resource reservation period, aperiodic resource reservation, SL-PRS resource indicator for first transmission, SL-PRS resource indicator for SL-PRS retransmission, PHY layer reference signal received power (RSRP) report, or RRC layer RSRP report.

[0104] In some examples, the method involves mapping an SL-PRS sequence to resource elements in a slot on an antenna port based on a configured or preconfigured comb size and comb offset, where the comb offset is defined relative to a reference point. The antenna port may be different from the antenna port used to transmit the PSCCH. The reference point may be a common reference point A associated with Uu link communication, the lowest physical resource block or the lowest subcarrier in the sidelink bandwidth portion of the dedicated resource pool, or a configured or predefined offset from the lowest physical resource block or the lowest subcarrier in the sidelink bandwidth portion of the dedicated resource pool.

[0105] Figure 13 is a flowchart outlining an exemplary method 1300 for transmitting SL-PRS based on resource allocation from a network. Method 1300 may be performed by TX UE 401 and / or 1110 in Figures 4 and 11, respectively. Method 1310 includes selecting a side-link positioning reference signal (SL-PRS) resource based on resource allocation received from the network. Method 1320 includes transmitting SL-PRS on the selected SL-PRS resource.

[0106] Resource allocation may represent one or more of the following: shared resource pool index, dedicated resource pool index, time gap, SCI format 1-A / time resource allocation, configuration index, sub-channel index for the first SL-PRS transmission, sub-channel index for the SL-PRS retransmission, SL-PRS resource index for the first SL-PRS transmission, or SL-PRS resource index for the SL-PRS retransmission.

[0107] In some embodiments, resource allocation corresponds to downlink control information (DCI) that identifies the UE based on an SL-PRS radio network temporary identifier (RNTI), or to an SL-PRS configured scheduled RNTI allocated to the UE based on a dedicated resource pool. In other embodiments, resource allocation corresponds to a configured grant that indicates one or more of the following: an SL-PRS configured grant configuration index, an SL-PRS configured grant duration, a configured grant time resource, a configured grant time offset, an SL-PRS time reference system frame number, or a dedicated resource pool identifier.

[0108] Figure 14 is a flowchart outlining an exemplary method 1400 for transmitting SL-PRS using a dedicated resource pool. Method 1400 may be performed by TX UE 401 and / or 1110 in Figures 4 and 11, respectively. Method 1410 includes exchanging unicast messages with a second UE using resources from a shared resource pool. Method 1420 includes transmitting or receiving a side-link positioning reference signal (SL-PRS) using SL-PRS resources from a dedicated resource pool, which is linked to a shared resource pool by configuration or preconfiguration.

[0109] In some examples, the method includes establishing a unicast link with a second UE using resources from a shared resource pool, receiving a destination identifier (ID) or source ID from the second UE using resources from the shared resource pool, and transmitting or receiving SL-PRS based on the received destination ID or source ID. The method may also include receiving UE capability information or open-loop power configuration using the unicast link. The method may also include transmitting SL data using resources from a dedicated resource pool, a different shared resource pool linked to a dedicated resource pool, or a different dedicated resource pool.

[0110] Figure 15 is a flowchart outlining an exemplary method 1500 for requesting SL-PRS transmission using a dedicated resource pool. Method 1500 may be performed by RX UE 402 and / or 1120 in Figures 4 and 11, respectively. Method 1510 includes determining the MAC layer destination ID of the transmit (TX) UE. As shown in Figure 11, Method 1510 may include establishing a unicast link with the TX UE using a shared resource pool linked to a dedicated resource pool, the UE being configured or pre-configured with a shared resource pool or a dedicated resource pool, and determining the MAC layer destination ID based on the unicast link. A shared resource pool may be linked to two or more dedicated resource pools, and / or a dedicated resource pool may be linked to two or more shared resource pools.

[0111] In another example, the method includes determining the MAC layer source ID based on either a dedicated resource pool or a shared resource pool. Shared and dedicated resource pools may be identified by a resource pool identifier (ID), a resource pool configuration indicated in an information element, or resource pool time and frequency resources. The method may include determining a shared resource pool based on the configuration or preconfiguration of a dedicated resource pool. The method may include determining a dedicated resource pool based on the configuration or preconfiguration of a shared resource pool. The method may include determining shared and dedicated resource pools based on RRC signaling, PC5-RRC signaling, or positioning protocol signaling. In yet another example, the method includes determining shared and dedicated resource pools based on RRC signaling, PC5-RRC signaling, or positioning protocol signaling.

[0112] Alternatively, the method may include determining the MAC Layer destination ID by pre-configuration or based on a positioning application ID assigned to the TX UE by the UE. In other examples, the method may include determining the MAC Layer destination ID based on pre-configuration of a dedicated resource pool, signaling from the network constituting the dedicated resource pool, or a policy control function (PCF).

[0113] The method includes, in 1520, deriving a PHY layer destination ID based on a MAC layer destination ID. In 1530, sidelink control information (SCI) containing a request for an SL-PRS is sent to the TX UE. In some examples, the method includes sending an SCI using a resource in a dedicated resource pool to request an SL-PRS in a resource in a dedicated resource pool or in a resource in a shared resource pool. In some examples, the method includes sending an SCI using a resource in a shared resource pool to request an SL-PRS in a resource in a dedicated resource pool or in a resource in a shared resource pool. In 1540, the method includes receiving an SL-PRS from the TX UE on a resource in a dedicated resource pool.

[0114] Figure 16 is a flowchart outlining an exemplary method 1600 for transmitting an SL-PRS based on a configuration by a higher layer. Method 1600 may be performed by TX UEs 401 and / or 1110 in Figures 4 and 11, respectively. The relevant method is shown in Figure 11. The method includes, in 1610, receiving a PHY layer request from the RX UE for a sidelink positioning reference signal (SL-PRS). The method includes, in 1620, in response to the request, providing an intermediate request to the higher layer based on the request, the intermediate request corresponding to a request to the higher layer for the UE to transmit the SL-PRS to the RX UE in accordance with the request. The higher layer may be a network device implementing the Sidelink Positioning Protocol (SPP), New Radio (NR) Positioning Protocol A (NRPPa), or Long-Term Evolution (LTE) Positioning Protocol (LPP). In 1630, in response to the signal from the higher layer, the SL-PRS is transmitted to the RX UE on a resource in a dedicated resource pool.

[0115] Figure 17 is a flowchart outlining an exemplary method 1700 for determining SL-PRS transmit power. Method 1700 may be performed by TX UE 401 and / or 1110 in Figures 4 and 11, respectively. Method 1710 includes determining the sidelink positioning reference signal SL-PRS transmit power based on the sidelink (SL) path loss between the UE and the receiving (RX) UE or the downlink (DL) path loss to the UE. Method 1720 includes transmitting the SL-PRS based on the determined SL-PRS transmit power.

[0116] The method may include determining the SL-PRS transmit power based on DL path loss when the UE is within network coverage, or causing the UE to transmit SL-PRS using maximum power when the UE is not within network coverage. The method may include determining the SL-PRS transmit power based on SL path loss, which is determined based on Reference Signal Received Power (RSRP) measurements received from the RX UE on a resource in a shared resource pool linked to a dedicated resource pool configured for the UE for SL-PRS. In this example, the method may include using a resource in the shared resource pool to initiate a unicast link with the RX UE, and the RSRP measurements are received over the unicast link. In some examples, the method includes using the PSCCH resource in the shared resource pool to receive the RSRP measurements. The shared resource pool may be pre-configured or configured to be linked to a dedicated resource pool.

[0117] In some examples, the method includes receiving an RRC layer RSRP report or a PHY layer RSRP report. The method may also include determining the SL-PRS path loss based on one or more reference signal received power (RSRP) measurements of the PHY layer signal performed by the RX UE.

[0118] The method may include receiving RSRP measurements from the RX UE and processing the received RSRP measurements to determine a filtered RSRP value, with the SL-PRS transmit power based on the filtered RSRP value. The method may include receiving one or more RSRP measurements in single-stage sidelink control information (SCI). The method may include receiving a filtered RSRP value, with the SL-PRS transmit power based on the filtered RSRP value.

[0119] The method may include transmitting a single-stage SCI to the RX UE, which indicates the reference signal transmit power of the reference signal to be transmitted to the RX UE, for use by the RX in calculating the SL path loss.

[0120] In other examples, the method may include determining the SL-PRS transmit power based on the transmit power associated with transmitting a physical sidelink shared channel (PSSCH) transmit. The method may include determining the transmit power of an SL-PRS symbol as equivalent to the total transmit power of PSCCHs in a dedicated resource pool. The method may include determining the transmit power of an SL-PRS resource element as equivalent to the transmit power of each resource element of PSCCHs in a dedicated resource pool.

[0121] Figure 18 is a flowchart outlining an exemplary method 1800 for transmitting an SL-PRS using a dedicated resource pool. Method 1800 may be performed by TX UE401 and / or 1110 in Figures 4 and 11, respectively. Method 1810 includes transmitting a side-link positioning reference signal (SL-PRS). Method 1820 includes transmitting an instruction for the transmission time of the SL-PRS or a timestamp associated with the SL-PRS.

[0122] In some examples, the transmission time or timestamp is reported based on time-domain units (Tc), and the quantization of Tc is configured or pre-configured for all resource pools or per resource pool. In some examples, the transmission time or timestamp is reported in absolute time duration corresponding to a subframe or frame, and the quantization of Tc is fixed. In other examples, the transmission time or timestamp is reported in absolute time duration corresponding to a slot base, and the quantization of Tc is determined based on the subcarrier interval. The absolute time duration is 1 millisecond and can range from -0.5 milliseconds to 0.5 milliseconds.

[0123] The method may include reporting the SL-PRS transmission time based on a timestamp associated with the OFDM symbol of the start of the SL-PRS transmission or measurement. The timestamp may indicate the system frame number or direct frame number of the OFDM symbol of the start of the SL-PRS transmission or measurement.

[0124] The above are several flowcharts outlining exemplary methods and message exchanges. In this description and the attached claims, the use of the term “determine” with respect to certain entities (e.g., parameters, variables, etc.) when describing steps or functions of a method should be interpreted broadly. For example, “determine” should be interpreted to include, for example, receiving and parsing communications encoding an entity or a value of an entity. “Determine” should be interpreted to include accessing and reading from memory (e.g., lookup tables, registers, device memory, remote memory, etc.) that stores an entity or a value of an entity. “Determine” should be interpreted to include calculating or deriving an entity or a value of an entity based on other quantities or entities. “Determine” should be interpreted to include any method of inferring or identifying an entity or a value of an entity.

[0125] As used herein, the term "identify" should be interpreted broadly to encompass any method of determining an entity or the value of an entity when used in relation to such entity or value. For example, the term "identify" should be interpreted to encompass, for example, receiving and parsing communications that encode an entity or the value of an entity. The term "identify" should be interpreted to encompass accessing and reading from memory (e.g., device queues, lookup tables, registers, device memory, remote memory, etc.) that stores an entity or the value of an entity.

[0126] As used herein, the term "encode" should be interpreted broadly to encompass any method or technique for generating a data sequence or signal that communicates an entity to another component, when used in relation to any entity or the value of an entity.

[0127] As used herein, the term "select" should be interpreted broadly to encompass any method of determining an entity or a value of an entity from among several or a range of possible choices. For example, the term "select" should be interpreted to encompass accessing and reading from memory (e.g., a lookup table, register, device memory, remote memory, etc.) that stores an entity or a value of an entity, and returning one entity or a value of an entity from among the stored entities or values ​​of entities. The term "select" should be interpreted to mean applying one or more constraints or rules to a given set of parameters in order to determine an appropriate entity or a value of an entity. The term "select" should be interpreted broadly to encompass any method of selecting an entity based on one or more parameters or conditions.

[0128] As used herein, the term "derive" should be interpreted broadly when used in relation to any entity or value of an entity. "Derive" should be interpreted to include accessing and reading from memory (e.g., lookup tables, registers, device memory, remote memory, etc.) that stores some initial or base value, and performing operations and / or logical / mathematical operations on one or more values ​​to produce a derived entity or value of an entity. The term "derive" should be interpreted to include calculating or calculating an entity or value of an entity based on other quantities or entities. The term "derive" should be interpreted to include any method of inferring or identifying an entity or value of an entity.

[0129] As used herein, the term "indicate" should be interpreted broadly to encompass any means of communicating an entity or its value, explicitly or implicitly, when used in relation to any entity (e.g., a parameter or setting) or the value of an entity. For example, bits in a transmitted message may be used to explicitly encode an indicated value, or, by prior configuration, to encode an index or other indicator mapped to an indicated value. The absence of a field in a message may implicitly indicate the value of an entity based on prior configuration.

[0130] Figure 19 shows an exemplary network 1900 in one or more implementation forms described herein. The exemplary network 1900 may include UE1910-1, 1910-2, etc. (collectively referred to as "UE1910" and individually referred to as "UE1910"), a radio access network (RAN) 1920, a core network (CN) 1930, an application server 1940, and an external network 1950.

[0131] The exemplary Network 1900 systems and devices may operate in accordance with one or more communication standards, such as the 2nd generation (2G), 3rd generation (3G), 4th generation (4G) (e.g., Long-Term Evolution (LTE)), and / or 5th generation (5G) (e.g., New Radio (NR)) communication standards of the 3rd Generation Partnership Project (3GPP). Additionally or alternatively, one or more of the exemplary Network 1900 systems and devices may operate in accordance with other communication standards and protocols described herein, including future versions or generations of 3GPP standards (e.g., 6th generation (6G) standards, 7th generation (7G) standards, etc.), and IEEE standards (e.g., Wireless Metropolitan Area Network (WMAN), Worldwide Interoperability for Microwave Access (WiMAX), etc.).

[0132] As illustrated, an example of a UE1910 may be a smartphone (e.g., a handheld touchscreen mobile computing device capable of connecting to one or more wireless communication networks). Additionally or alternatively, a UE1910 may include other types of wirelessly communicating mobile or non-mobile computing devices, such as personal digital assistants (PDAs), pagers, laptop computers, desktop computers, wireless handsets, and portable watches. In some implementations, a UE1910 may include an Internet of Things (IoT) device (or IoT UE) that may have a network access layer designed for low-power IoT applications that utilize short-lived UE connections. Additionally or alternatively, an IoT UE may utilize one or more types of technologies, such as machine-to-machine (M2M) communication, or machine-type communication (MTC) (for example, exchanging data with an MTC server or other device via a Public Land Mobile Network (PLMN)), proximity-based service (ProSe), or device-to-device (D2D) communication, sensor networks, or IoT networks. Depending on the scenario, the M2M or MTC data exchange may be machine-initiated, and the IoT network may involve interconnecting IoT UEs (which may include uniquely identifiable embedded computing devices within the internet infrastructure) with short-lived connections. In some scenarios, the IoT UE may run background applications (e.g., keep-alive messages, status updates, etc.) to facilitate connectivity within the IoT network.

[0133] UE1910 may use stored SL-PRS instructions and information to perform one or more of the solutions disclosed with reference to Figures 1 to 18 in order to transmit or receive SL-PRS with another UE1910 via wireless channel 1912, each of which may have a physical communication interface / layer. Connections may include M2M connections, MTC connections, D2D connections, SL connections, etc. Connections may involve a PC5 interface. In some implementations, UE1910s may be configured to discover each other, negotiate wireless resources between them, and establish connections between them without intervention or communication with a RAN node 1922 or another type of network node. In some implementations, discovery, authentication, resource negotiation, registration, etc. may involve communication with a RAN node 1922 or another type of network node.

[0134] UE1910 may use one or more wireless channels 1912 to communicate with each other. As described herein, UE1910-1 may communicate with RAN node 1922 to request SL resources. RAN node 1922 may respond to the request by providing UE1910 with a dynamic grant (DG) or configured grant (CG) regarding the SL resources. A DG may be accompanied by a grant based on a grant request from UE1910. A CG may be accompanied by a resource grant without a grant request and may be based on the type of service being provided (e.g., a service with strict timing or latency requirements). UE1910 may perform a Clear Channel Assessment (CCA) procedure based on the DG or CG, select an SL resource based on the CCA procedure and the DG or CG, and communicate with another UE1910 based on the SL resource. UE1910 may communicate with RAN node 1922 using licensed frequency bands and with other UE1910 using unlicensed frequency bands.

[0135] UE1910 can communicate with RAN1920 and establish a connection with it (e.g., be communicatively coupled), which may include one or more wireless channels 1914-1 and 1914-2, each of which may have a physical communication interface / layer, also called a Uu interface or link.

[0136] As described herein, the UE1910 may receive and store one or more configurations, instructions, and / or other information to enable SL-U communications with quality and priority standards. PQI may be determined and used to indicate QoS associated with SL-U communications (e.g., channels, data flows, etc.). Similarly, L1 priority values ​​may be determined and used to indicate priority for SL-U transmissions, SL-U channels, SL-U data, etc. PQI and / or L1 priority values ​​may be mapped to CAPC values, and PQI, L1 priority, and / or CAPC may indicate SL channel occupancy time (COT) sharing, maximum (MCOT), timing gap for COT sharing, LBT configuration, traffic, and channel priority, etc.

[0137] As shown in the figure, UE1910 may further, or alternatively, connect to AP1916 via a connection interface 1918 which may include an air interface that enables UE1910 to communicate with access point (AP) 1916. AP1916 may comprise a wireless local area network (WLAN), WLAN nodes, WLAN termination points, etc. Connection 1918 may comprise a local wireless connection such as a connection that conforms to any IEEE 702.11 protocol, and AP1916 may comprise a Wireless Fidelity (Wi-Fi®) router or other AP. Although not explicitly shown in Figure 19, AP1916 may connect to another network (e.g., the Internet) without connecting to RAN1920 or CN1930.

[0138] RAN1920 may include one or more RAN nodes 1922-1 and 1922-2 (collectively referred to as RAN node 1922, and individually referred to as RAN node 1922) that enable channels 1914-1 and 1914-2 to be established between UE1910 and RAN1920. RAN node 1922 may include network access points configured to provide radio baseband functionality for data and / or voice connectivity between users and the network, based on one or more of the communication technologies described herein (e.g., 2G, 3G, 4G, 5G, WiFi, etc.). Thus, for example, RAN nodes may be E-UTRAN node B (e.g., extended node B, e-node B, eNB, 4G base station, etc.), next-generation base stations (e.g., 5G base station, NR base station, next-generation eNB (gNB), etc.). RAN node 1922 may include roadside units (RSUs), transmit / receive points (TRxP or TRP), and one or more other types of ground stations (e.g., ground access points). In some scenarios, RAN node 1922 may be a dedicated physical device such as a macrocell base station and / or a low-power (LP) base station to provide a smaller coverage area, smaller user capacity, or wider bandwidth compared to a macrocell, such as a femtocell or picocell.

[0139] In some implementations, the downlink resource grid may be used for downlink transmissions from any of the RAN nodes 1922 to UE1910, and uplink transmissions may utilize similar techniques. The grid can be a time-frequency grid (e.g., a resource grid or time-frequency resource grid) representing the physical resources of the downlink within each slot. Such a time-frequency plane representation is a common method for OFDM systems, making the allocation of radio resources intuitive. Each column and row of the resource grid corresponds to one OFDM symbol and one OFDM subcarrier, respectively. The duration of the resource grid in the time domain corresponds to one slot in a radio frame. The smallest time-frequency unit of the resource grid is denoted as a resource element. Each resource grid comprises a resource block, which represents the mapping of a particular physical channel to a resource element. Each resource block can comprise a set of resource elements (REs), which in the frequency domain can represent the minimum amount of resources currently available for allocation. There are several different physical downlink channels that are transmitted using such resource blocks.

[0140] RAN nodes 1922 may be configured to communicate with each other via interface 1923. In implementations where the system is an LTE system, interface 1923 may be an X2 interface. In an NR system, interface 1923 may be an Xn interface. An X2 interface may be defined between two or more RAN nodes 1922 (e.g., two or more eNBs / gNBs or a combination thereof) connected to an evolved packet core (EPC) or CN1930, and / or between two eNBs connected to the EPC.

[0141] As illustrated, RAN1920 may be connected to CN1930 (e.g., communicatively coupled). CN1930 may comprise multiple network elements 1932 configured to provide various data and telecommunications services to customers / subscribers (e.g., users of UE1910) connected to CN1930 via RAN1920. In some implementations, CN1930 may include an Evolutionary Packet Core (EPC), a 5G CN, and / or one or more additional or alternative types of CNs. Functions provided by CN1930 include a Policy Control Function (PCF) and a Location Management Function (LMF). The components of CN1930 may be implemented on a single physical node or separate physical nodes, including components for reading and executing instructions from machine-readable or computer-readable media (e.g., non-temporary machine-readable storage media).

[0142] As shown in the figure, CN1930, application server 1940, and external network 1950 may be connected to each other via interfaces 1934, 1936, and 1938, which may include IP network interfaces. The application server may include a server that performs positioning-related services, such as a V2X server, for UE1910.

[0143] Figure 20 is a diagram illustrating one embodiment of the components of a network device according to one or more implementations described herein. In some implementations, device 2000 may include, at least as shown, a jointly coupled application circuit configuration 2002, a baseband circuit configuration 2004, an RF circuit configuration 2006, a front-end module (FEM) circuit configuration 2008, one or more antennas 2010, and a power management circuitry (PMC) 2012. The components of device 2000 shown may be included in a UE or RAN node. In some implementations, device 2000 may include fewer components (for example, a RAN node may not utilize the application circuit configuration 2002 and instead include a processor / controller that processes IP data received from a CN or Evolved Packet Core (EPC)). In some implementations, device 2000 may include additional elements such as memory / storage, a display, a camera, sensors (including one or more temperature sensors, such as a single temperature sensor or multiple temperature sensors located in different locations within device 2000), or input / output (I / O) interfaces. In other implementations, the components described below may be contained in two or more devices (for example, the above circuit configuration may be contained separately in two or more devices in a Cloud-RAN (C-RAN) implementation).

[0144] The application circuit configuration 2002 may include one or more application processors. For example, the application circuit configuration 2002 may include, but is not limited to, one or more single-core processors or multi-core processors. The processor(s) may include any combination of general-purpose processors and dedicated processors (e.g., graphics processors, application processors, etc.). The processors may be coupled to memory / storage or may include memory / storage and may be configured to execute instructions stored in memory / storage to enable various applications or operating systems to run on device 2000. In some implementations, the processors of the application circuit configuration 2002 may process IP data packets received from the EPC.

[0145] The baseband circuit configuration 2004 may include, but is not limited to, one or more single-core processors or multi-core processors. The baseband circuit configuration 2004 may include one or more baseband processors or control logic that process baseband signals received from the receiving signal path of the RF circuit configuration 2006 and generate baseband signals for the transmitting signal path of the RF circuit configuration 2006. The baseband circuit configuration 2004 may interface with the application circuit configuration 2002 for baseband signal generation and processing, and for controlling the operation of the RF circuit configuration 2006. For example, in some implementations, the baseband circuit configuration 2004 may include a 3G baseband processor 2004A, a 4G baseband processor 2004B, a 5G baseband processor 2004C, or another baseband processor(s) 2004D for other existing, developing, or future generations (e.g., 5G, 6G, etc.).

[0146] The baseband circuit configuration 2004 (for example, one or more of the baseband processors 2004A to 2004D) can handle various radio control functions that enable communication with one or more radio networks via the RF circuit configuration 2006. In other implementations, some or all of the functions of the baseband processors 2004A to 2004D may be contained in modules stored in memory 2004G and executed via a Central Processing Unit (CPU) 2004E. In some implementations, the baseband circuit configuration 2004 may include one or more audio digital signal processors (one or more) (Digital Signal Processors, DSPs) 2004F.

[0147] In some implementations, memory 2004G may receive and / or store SL-PRS instructions and information that cause device 2000 to operate as TX UE and / or RX UE when transmitting or receiving SL-PRS, as disclosed with reference to Figures 1 to 18.

[0148] The RF circuit configuration 2006 can enable communication with a wireless network using modulated electromagnetic radiation over a non-solid medium. In various implementations, the RF circuit configuration 2006 may include switches, filters, amplifiers, etc., to facilitate communication with the wireless network. The RF circuit configuration 2006 may include a received signal path that includes a circuit configuration to downconvert the RF signal received from the FEM circuit configuration 2008 and provide the baseband signal to the baseband circuit configuration 2004. The RF circuit configuration 2006 may also include a transmitted signal path that includes a circuit configuration to upconvert the baseband signal provided by the baseband circuit configuration 2004 and provide the RF output signal to the FEM circuit configuration 2008 for transmission.

[0149] In some implementations, the receive signal path of RF circuit configuration 2006 may include a mixer circuit configuration 2006A, an amplifier circuit configuration 2006B, and a filter circuit configuration 2006C. In some implementations, the transmit signal path of RF circuit configuration 2006 may include a filter circuit configuration 2006C and a mixer circuit configuration 2006A. RF circuit configuration 2006 may also include a combiner circuit configuration 2006D that combines the frequencies used by the mixer circuit configuration 2006A of the receive signal path and the transmit signal path.

[0150] The embodiments described herein may include subject matter such as a method, means for performing the operation or block of the method, and at least one machine-readable medium containing executable instructions that cause the machine to perform the operation of a method or apparatus or system for simultaneous communication using the multiplexing techniques described in the implementations and embodiments, when performed by a machine or circuit configuration (for example, a processor with memory, an Application-Specific Integrated Circuit (ASIC), a Field Programmable Gate Array (FPGA), etc.).

[0151] Embodiment 1 is a user device (UE) including memory and a baseband processor. When the baseband processor executes an instruction stored in memory, it is configured to cause the UE to select a sidelink positioning reference signal (SL-PRS) resource from a dedicated resource pool which includes candidate physical sidelink control channel (PSCCH) resources configured to carry single-stage sidelink control information (SCI) and candidate SL-PRS resources, but does not include candidate resources for physical sidelink shared channel (PSSCH) transmission, and to transmit SL-PRS on the selected SL-PRS resource.

[0152] Embodiment 2 includes the subject matter of Embodiment 1, with or without optional elements, wherein the baseband processor is configured to select periodic SL-PRS resources that occur within the same frequency domain resource in the same slot for each SL-PRS resource period during the reserved period.

[0153] Example 3 includes the subject matter of Example 1, with or without optional elements, wherein the baseband processor is configured to select aperiodic SL-PRS resources.

[0154] Example 4 includes the subject matter of Example 1, with or without optional elements, and each candidate SL-PRS resource is represented by a slot index and a subchannel index, or a slot index and an SL-PRS resource index.

[0155] Example 5 includes the subject matter of Example 4, with or without optional elements, wherein PSCCH resources in slots within a dedicated resource pool are indexed with respect to frequency location, and SL-PRS resources in slots within a dedicated resource pool are indexed in the following order: first by frequency within the SL-PRS resource, second by the SL-PRS resource, or first by symbol within the SL-PRS resource, second by frequency within the SL-RS resource, third by the SL-PRS resource, or first by symbol within the SL-PRS resource, second by the SL-PRS resource, third by frequency.

[0156] Example 6 includes the subject matter of Example 4, with or without optional elements, wherein each PSCCH resource is mapped to one SL-PRS resource, and the mapped SL-PRS resource index is either the same as the PSCCH resource index or different from the PSCCH resource index.

[0157] Example 7 includes the subject matter of Example 4, with or without optional elements, wherein each PSCCH is mapped to a set of SL-PRS resources, and the baseband processor is configured to transmit a selected instruction from the set of SL-PRS resources in a single-stage SCI carried by the PSCCH resources.

[0158] Example 8 includes the subject matter of Example 7, with or without optional elements, and the set of SL-PRS resources has a contiguous SL-PRS resource index.

[0159] Example 9 includes the subject matter of Example 7, with or without optional elements, and the set of SL-PRS resources has an interleaved SL-PRS resource index.

[0160] Example 10 includes the subject matter of Example 7, with or without optional elements, wherein the baseband processor is configured to select an SL-PRS resource from a set of SL-PRS resources based on one or more of the following: priority, resource reservation periodicity, SL channel busy rate, or SL channel occupancy rate associated with the SL-PRS.

[0161] Embodiment 11 includes the subject matter of Embodiment 1, with or without optional elements, wherein the baseband processor is configured to cause the UE to select an SL-PRS resource from the dedicated resource pool by measuring the reference signal received power (RSRP) of a single-stage SCI in a candidate PSCCH of the dedicated resource pool, decoding the single-stage SCI to determine the resource reservation period and priority of the individual SL-PRS associated with the individual SCI, and excluding candidate resources associated with a single-stage SCI having an RSRP higher than a threshold from the candidate resource pool.

[0162] Example 12 includes the subject matter of Example 11, with optional elements included or omitted, and the threshold is selected based on the priority shown in the single-stage SCI or the SL-PRS priority.

[0163] Embodiment 13 includes the subject matter of Embodiment 1, with or without optional elements, wherein the baseband processor decodes a single-stage SCI in the preemption time interval prior to the selected SL-PRS resource to determine whether the selected SL-PRS resource is reserved for a higher-priority SL-PRS, and is configured to refrain from transmitting an SL-PRS if the selected SL-PRS resource is reserved for a higher-priority SL-PRS.

[0164] Example 14 includes the subject matter of Example 13, with or without optional elements, wherein the baseband processor is configured to decode a single-stage SCI in the same subchannel as the selected SL-PRS resource and to compare the priority of the SL-PRS associated with the single-stage SCI with the priority of the transmitted SL-PRS.

[0165] Example 15 includes the subject matter of Example 13, with or without optional elements, wherein the baseband processor is configured to decode single-stage SCIs in all subchannels of a dedicated resource pool and to compare the priority of the individual SL-PRS associated with the single-stage SCI with the priority of the transmitted SL-PRS.

[0166] Example 16 includes the subject matter of Example 1, with or without optional elements, wherein the single-stage SCI includes one or more of the following indicators: source ID for UE, destination ID for receiving (RX) UE, associated SL-PRS priority, resource reservation period, aperiodic resource reservation, SL-PRS resource indicator for first transmission, SL-PRS resource indicator for SL-PRS retransmission, PHY layer reference signal received power (RSRP) report, or RRC layer RSRP report.

[0167] Example 17 includes the subject matter of Example 1, with or without optional elements, wherein the baseband processor is configured to map SL-PRS sequences to resource elements in slots on the antenna port based on configured or preconfigured comb size and comb offset, the comb offset being defined with respect to a reference point.

[0168] Example 18 includes the subject matter of Example 17, with or without optional elements, and the antenna port is different from the antenna port used to transmit the PSCCH.

[0169] Example 19 includes the subject matter of Example 17, with or without optional elements, wherein the reference point is a common reference point A associated with Uu link communication, the lowest physical resource block or the lowest subcarrier in the sidelink bandwidth portion of the dedicated resource pool, or an offset composed of or predefined from the lowest physical resource block or the lowest subcarrier in the sidelink bandwidth portion of the dedicated resource pool.

[0170] Example 20 is a user device (UE) that includes memory and a baseband processor. The baseband processor is configured to, when executing instructions stored in memory, cause the UE to select a sidelink positioning reference signal (SL-PRS) resource based on resource allocation received from the network and to transmit SL-PRS at the selected SL-PRS resource.

[0171] Example 21 includes the subject matter of Example 20, with or without optional elements, wherein the resource allocation represents one or more of the following: shared resource pool index, dedicated resource pool index, time gap, SCI format 1-A / time resource allocation, configuration index, subchannel index for the first SL-PRS transmission, subchannel index for the SL-PRS retransmission, SL-PRS resource index for the first SL-PRS transmission, and SL-PRS resource index for the SL-PRS retransmission.

[0172] Example 22 includes the subject matter of Example 21, with or without optional elements, wherein resource allocation includes downlink control information (DCI) that identifies the UE based on an SL-PRS radio network temporary identifier (RNTI), or an SL-PRS configured scheduled RNTI that is allocated to the UE based on a dedicated resource pool.

[0173] Example 23 includes the subject matter of Example 21, with or without optional elements, wherein the resource allocation includes a configured grant that indicates one or more of the following: SL-PRS configured grant configuration index, SL-PRS configured grant duration, configured grant time resource, configured grant time offset, SL-PRS time reference system frame number, and dedicated resource pool identifier.

[0174] Embodiment 24 is a user equipment (UE) including memory and a baseband processor. The baseband processor is configured to cause the UE to exchange unicast messages with a second UE using resources from a shared resource pool and to transmit or receive SL-PRS using sidelink positioning reference signal (SL-PRS) resources from a dedicated resource pool, which is linked to the shared resource pool by configuration or preconfiguration.

[0175] Example 25 includes the subject matter of Example 24, with or without optional elements, wherein the baseband processor is configured to cause the UE to establish a unicast link with a second UE using resources from a shared resource pool, to receive a destination identifier (ID) or source ID from the second UE using resources from the shared resource pool, and to transmit or receive SL-PRS based on the received destination ID or source ID.

[0176] Example 26 includes the subject matter of Example 25, with or without optional elements, wherein the baseband processor is configured to cause the UE to transmit or receive UE capability information or open-loop power configuration using a unicast link.

[0177] Example 27 includes the subject matter of Example 24, with or without optional elements, wherein the baseband processor is configured to cause the UE to transmit SL data using resources from a dedicated resource pool, different shared resource pools linked to a dedicated resource pool, or different dedicated resource pools.

[0178] Embodiment 28 is a user device (UE) that includes memory and a baseband processor. The baseband processor is configured to, when executing instructions stored in memory, cause the UE to determine the MAC layer destination ID of the transmit (TX) UE, derive the PHY layer destination ID based on the MAC layer destination ID, send a PHY layer request for a sidelink positioning reference signal (SL-PRS) to the TX UE, and receive the SL-PRS from the TX UE on the resources of a dedicated resource pool.

[0179] Example 29 comprises the subject matter of Example 28, with or without optional elements, wherein the baseband processor is configured to establish a unicast link with a TX UE using a shared resource pool linked to a dedicated resource pool, the UE being configured or pre-configured with the shared or dedicated resource pool, and to determine the MAC destination ID by establishing the link and determining the MAC layer destination ID based on the unicast link.

[0180] Example 30 includes the subject matter of Example 29, with optional elements included or omitted, and the shared resource pool is linked to two or more dedicated resource pools.

[0181] Example 31 includes the subject matter of Example 29, with optional elements included or omitted, and the dedicated resource pool is linked to two or more shared resource pools.

[0182] Example 32 includes the subject matter of Example 29, with or without optional elements, wherein the baseband processor is configured to determine the MAC layer source ID based on either a dedicated resource pool or a shared resource pool.

[0183] Example 33 includes the subject matter of Example 29, with or without optional elements, wherein shared resource pools and dedicated resource pools are identified by a resource pool identifier (ID), a resource pool configuration indicated in an information element, or resource pool time and frequency resources.

[0184] Example 34 includes the subject matter of Example 29, with or without optional elements, wherein the baseband processor is configured to determine a shared resource pool based on the configuration of a dedicated resource pool or a preconfiguration.

[0185] Example 35 includes the subject matter of Example 29, with or without optional elements, wherein the baseband processor is configured to determine a dedicated resource pool based on the configuration of a shared resource pool or a preconfiguration.

[0186] Example 36 includes the subject matter of Example 29, with or without optional elements, wherein the baseband processor is configured to determine shared and dedicated resource pools based on RRC signaling, PC5-RRC signaling, or positioning protocol signaling.

[0187] Example 37 includes the subject matter of Example 28, with or without optional elements, wherein the baseband processor is configured to determine the MAC layer destination ID based on a positioning application ID assigned to the TX UE by pre-configuration or by the UE.

[0188] Example 38 includes the subject matter of Example 28, with or without optional elements, wherein the baseband processor is configured to determine the MAC layer destination ID based on pre-configuration of a dedicated resource pool, signaling from the network constituting the dedicated resource pool, or a policy control function (PCF).

[0189] Example 39 includes the subject matter of Example 28, with or without optional elements, wherein the baseband processor is configured to cause the UE to transmit sidelink control information (SCI) including a request for SL-PRS.

[0190] Example 40 includes the subject matter of Example 39, with or without optional elements, wherein the baseband processor is configured to cause the UE to send an SCI using the resources of the dedicated resource pool to request an SL-PRS in the resources of the dedicated resource pool or an SL-PRS in the resources of the shared resource pool.

[0191] Example 41 includes the subject matter of Example 39, with or without optional elements, wherein the baseband processor is configured to cause the UE to send an SCI using the resources of the shared resource pool to request an SL-PRS in the resources of the dedicated resource pool or an SL-PRS in the resources of the shared resource pool.

[0192] Embodiment 42 is a user device (UE) including memory and a baseband processor. The baseband processor is configured to, when executing instructions stored in memory, cause the UE to receive a PHY layer request from the RX UE for a sidelink positioning reference signal (SL-PRS), and in response to the request, cause the higher layer to provide an intermediate request, which corresponds to a request to the higher layer for the UE to send the SL-PRS to the RX UE according to the request, and in response to the signal from the higher layer, cause the RX UE to send the SL-PRS on the resources of a dedicated resource pool.

[0193] Example 43 includes the subject matter of Example 42, with or without optional elements, and the upper layer includes a network device implementing Sidelink Positioning Protocol (SPP), New Radio (NR) Positioning Protocol A (NRPPa), or Long-Term Evolution (LTE) Positioning Protocol (LPP).

[0194] Embodiment 44 is a user device (UE) including memory and a baseband processor. The baseband processor is configured to, when executing instructions stored in memory, cause the UE to determine the sidelink positioning reference signal SL-PRS transmit power based on the sidelink (SL) path loss between the UE and the receiving (RX) UE or the downlink (DL) path loss between the UE and the UE, and to transmit the SL-PRS based on the determined SL-PRS transmit power.

[0195] Embodiment 45 includes the subject matter of Embodiment 44, with or without optional elements, wherein the baseband processor is configured to determine the SL-PRS transmit power based on DL path loss when the UE is within network coverage, or to cause the UE to transmit the SL-PRS using maximum power when the UE is not within network coverage.

[0196] Example 46 includes the subject matter of Example 44, with or without optional elements, wherein the baseband processor is configured to determine the SL-PRS transmit power based on the SL path loss, which is determined based on a reference signal received power (RSRP) measurement received from the RX UE on a shared resource pool resource linked to a dedicated resource pool configured for the UE for SL-PRS.

[0197] Example 47 includes the subject matter of Example 46, with or without optional elements, wherein the baseband processor is configured to use resources from a shared resource pool to initiate a unicast link with the RX UE, and RSRP measurements are received over the unicast link.

[0198] Example 48 includes the subject matter of Example 46, with or without optional elements, wherein the baseband processor is configured to use the PSCCH resource of the shared resource pool to receive RSRP measurements.

[0199] Example 49 includes the subject matter of Example 46, with or without optional elements, wherein the shared resource pool is pre-configured or configured to be linked to a dedicated resource pool.

[0200] Example 50 includes the subject matter of Example 44, with or without optional elements, wherein the baseband processor is configured to cause the UE to receive RRC layer RSRP reports or PHY layer RSRP reports.

[0201] Example 51 includes the subject matter of Example 44, with or without optional elements, wherein the baseband processor is configured to determine the SL path loss based on one or more reference signal received power (RSRP) measurements of the PHY layer signals performed by the RX UE.

[0202] Example 52 includes the subject matter of Example 44, with or without optional elements, wherein the baseband processor is configured to cause the UE to receive RSRP measurements from the RX UE and process the received RSRP measurements to determine a filtered RSRP value, and the SL-PRS transmit power is based on the filtered RSRP value.

[0203] Example 53 includes the subject matter of Example 52, with or without optional elements, wherein the baseband processor is configured to cause the UE to receive one or more RSRP measurements in single-stage sidelink control information (SCI).

[0204] Example 54 includes the subject matter of Example 44, with or without optional elements, wherein the baseband processor is configured to cause the UE to receive filtered RSRP values, and the SL-PRS transmit power is based on the filtered RSRP values.

[0205] Embodiment 55 includes the subject matter of Embodiment 54, with or without optional elements, wherein the baseband processor is configured to cause the UE to transmit a single-stage SCI to the RX UE indicating the reference signal transmit power of a reference signal that is sent to the RX UE by the RX to calculate the SL path loss.

[0206] Example 56 includes the subject matter of Example 44, with or without optional elements, wherein the baseband processor is configured to determine the SL-PRS transmit power based on the transmit power associated with transmitting a physical sidelink shared channel (PSSCH) transmit.

[0207] Example 57 includes the subject matter of Example 44, with or without optional elements, wherein the baseband processor is configured to determine that the transmit power of an SL-PRS symbol is equivalent to the total transmit power of a PSCCH in a dedicated resource pool.

[0208] Example 58 includes the subject matter of Example 44, with or without optional elements, wherein the baseband processor is configured to determine that the transmit power of an SL-PRS resource element is equivalent to the transmit power per resource element of a PSCCH in a dedicated resource pool.

[0209] Example 59 is a user device (UE) that includes memory and a baseband processor. The baseband processor is configured to cause the UE to transmit a sidelink positioning reference signal (SL-PRS) and an instruction for the transmission time of the SL-PRS or a timestamp associated with the SL-PRS when executing an instruction stored in memory.

[0210] Example 60 includes the subject matter of Example 59, with or without optional elements, where the transmission time or timestamp is reported based on time domain units (Tc), and the quantization of Tc is configured or preconfigured for all resource pools or per resource pool.

[0211] Example 61 includes the subject matter of Example 60, with or without optional elements, wherein the transmission time or timestamp is reported as an absolute time duration corresponding to a subframe or frame, and the quantization of Tc is fixed, or the transmission time or timestamp is reported as an absolute time duration corresponding to a slot basis, and the quantization of Tc is determined based on the subcarrier interval.

[0212] Example 62 includes the subject matter of Example 61, with or without optional elements, and the absolute time duration is 1 millisecond, ranging from -0.5 milliseconds to 0.5 milliseconds.

[0213] Example 63 includes the subject matter of Example 59, with or without optional elements, wherein the baseband processor is configured to report the SL-PRS transmission time based on a timestamp associated with the OFDM symbol of the start of the SL-PRS transmission or measurement.

[0214] Example 64 includes the subject matter of Example 63, with or without optional elements, and the timestamp indicates the system frame number or direct frame number of the OFDM symbol at the start of the SL-PRS transmission or measurement.

[0215] The above description of the illustrated embodiments, implementations, and aspects of the disclosed subject matter, including the contents of the abstract, is not intended to be exhaustive or to limit the disclosed aspects to the exact forms disclosed. Specific embodiments, implementations, and aspects are described herein for illustrative purposes, but those skilled in the art will see that various modifications are possible within the scope of such embodiments, implementations, and aspects.

[0216] Although the method is illustrated and described above as a series of actions or events, it should be understood that the illustrated order of such actions or events should not be interpreted restrictively. For example, some actions may occur in a different order and / or simultaneously with other actions or events not illustrated and / or described herein. In addition, not all illustrated actions are required to implement one or more aspects or embodiments of the disclosure. Furthermore, one or more of the actions shown herein may be performed in one or more separate actions and / or steps. In some embodiments, the method described above may be implemented on a computer-readable medium using instructions stored in memory. Many other embodiments and variations are possible within the scope of the claimed disclosure.

[0217] The term “coupled” is used throughout this specification. The term may cover connections, communications, or signaling paths that enable a functional relationship consistent with the description in this disclosure. For example, in the first example, device A is coupled to device B if device A generates signals to control device B to perform an action, or in the second example, device A is coupled to device B via intervening component C if intervening component C does not substantially alter the functional relationship between device A and device B so that device B is controlled by device A via a control signal generated by device A.

[0218] It is well understood that the use of personally identifiable information should be governed by privacy policies and practices that are generally recognized as meeting or exceeding industry or government requirements for maintaining user privacy. In particular, personally identifiable information data should be managed and handled in a manner that minimizes the risk of unintended or unauthorized access or use, and the nature of authorized use should be clearly indicated to the user.

Claims

1. User equipment (UE), Memory and A baseband processor, when executing an instruction stored in the memory, the UE, A dedicated resource pool includes candidate physical sidelink control channel (PSCCH) resources configured to carry single-stage sidelink control information (SCI) and candidate SL-PRS resources, but does not include candidate resources for physical sidelink shared channel (PSSCH) transmission. From this dedicated resource pool, a sidelink positioning reference signal (SL-PRS) resource is selected. The SL-PRS is transmitted using the selected SL-PRS resource. A baseband processor configured as follows, UE, equipped with [unclear / etc.].

2. The UE according to claim 1, wherein each candidate SL-PRS resource is represented by a slot index and a subchannel index, or a slot index and an SL-PRS resource index.

3. The PSCCH resources in the slots within the dedicated resource pool are indexed with respect to frequency location. The SL-PRS resources in the slots within the dedicated resource pool are indexed in the following order: firstly, by the frequency of the SL-PRS resource, and secondly, by the SL-PRS resource; or firstly, by the symbol within the SL-PRS resource, secondly, by the frequency within the SL-RS resource, and thirdly, by the SL-PRS resource; or firstly, by the symbol within the SL-PRS resource, secondly, by the SL-PRS resource, and thirdly, by the frequency. The UE according to claim 2.

4. The UE according to claim 2, wherein each PSCCH resource is mapped to one SL-PRS resource, and the mapped SL-PRS resource index is the same as the PSCCH resource index, or the mapped SL-PRS resource index is different from the PSCCH resource index.

5. The UE according to claim 2, wherein each PSCCH is mapped to a set of SL-PRS resources, and the baseband processor is configured to transmit a selected instruction from the set of SL-PRS resources in a single-stage SCI carried by the PSCCH resources.

6. The baseband processor provides the UE with The measurement of the reference signal received power (RSRP) of the single-stage SCI in the candidate PSCCH of the dedicated resource pool, The single-stage SCI is decoded to determine the resource reservation period and priority of the individual SL-PRS associated with the individual SCI, Excluding candidate resources associated with single-stage SCIs having an RSRP higher than the threshold from the candidate resource pool, The UE according to claim 1, configured to allow the user to select an SL-PRS resource from the dedicated resource pool.

7. The UE according to claim 6, wherein the threshold is selected based on the priority indicated in the single-stage SCI or the priority of the SL-PRS.

8. The UE according to claim 1, wherein the single-stage SCI includes one or more of the following indicators: a source ID for the UE, a destination ID for the receiving (RX) UE, the priority of the associated SL-PRS, a resource reservation period, a non-periodic resource reservation, an SL-PRS resource indicator for the first transmission, an SL-PRS resource indicator for the retransmission of the SL-PRS, a PHY layer reference signal received power (RSRP) report, or an RRC layer RSRP report.

9. User equipment (UE), Memory and A baseband processor, when executing an instruction stored in the memory, the UE, Based on the resource allocation received from the network, select a Sidelink Positioning Reference Signal (SL-PRS) resource. The SL-PRS is transmitted using the selected SL-PRS resource. A baseband processor configured as follows, UE, equipped with [unclear / etc.].

10. The UE according to claim 9, wherein the resource allocation includes downlink control information (DCI) that identifies the UE based on an SL-PRS radio network temporary identifier (RNTI), or an SL-PRS configured scheduled RNTI that is allocated to the UE based on a dedicated resource pool.

11. The UE according to claim 9, wherein the resource allocation includes a configured grant indicating one or more of the following: an SL-PRS configured grant configuration index, an SL-PRS configured grant period, a time resource for the configured grant, a time offset for the configured grant, an SL-PRS time reference system frame number, and a dedicated resource pool identifier.

12. A user device (UE) comprising memory and a baseband processor, wherein when the baseband processor executes an instruction stored in the memory, the UE, Use resources from the shared resource pool to exchange unicast messages with the second UE. A dedicated resource pool, which is linked to the shared resource pool by configuration or preconfiguration, uses its Sidelink Positioning Reference Signal (SL-PRS) resource to transmit or receive SL-PRS. UE is structured in such a way.

13. The baseband processor is connected to the UE, Using the resources of the shared resource pool, establish a unicast link with the second UE. Using the resources of the shared resource pool, the destination identifier (ID) or source ID is received from the second UE. Based on the received destination ID or source ID, SL-PRS is transmitted or received. The UE according to claim 12, configured as described above.

14. The UE according to claim 13, wherein the baseband processor is configured to cause the UE to transmit or receive UE capability information or open-loop power configuration using the unicast link.

15. A user device (UE) comprising memory and a baseband processor, wherein when the baseband processor executes an instruction stored in the memory, the UE, Determine the MAC layer destination ID of the transmit (TX) UE. Based on the MAC layer destination ID, the PHY layer destination ID is derived. The TX UE is instructed to send a PHY layer request regarding the sidelink positioning reference signal (SL-PRS). The TX UE receives SL-PRS on the resources of the dedicated resource pool. UE is structured in such a way.

16. The baseband processor uses the MAC destination ID to Establishing a unicast link with a TX UE using a shared resource pool linked to the dedicated resource pool, wherein the UE is composed of or pre-configured with the shared resource pool or the dedicated resource pool. The MAC layer destination ID is determined based on the unicast link, The UE according to claim 15, configured to be determined by

17. The UE according to claim 16, wherein the baseband processor is configured to determine the MAC layer source ID based on either the dedicated resource pool or the shared resource pool.

18. The UE according to claim 15, wherein the baseband processor is configured to determine the MAC layer destination ID by pre-configuration or based on a positioning application ID assigned to the TX UE by the UE.

19. The UE according to claim 15, wherein the baseband processor is configured to determine the MAC layer destination ID based on the pre-configuration of the dedicated resource pool, signaling from the network constituting the dedicated resource pool, or a policy control function (PCF).

20. The UE according to claim 15, wherein the baseband processor is configured to cause the UE to transmit sidelink control information (SCI) including the request for SL-PRS.

21. A user device (UE) comprising memory and a baseband processor, wherein when the baseband processor executes an instruction stored in the memory, the UE, The system receives a PHY layer request from the RX UE regarding the Sidelink Positioning Reference Signal (SL-PRS). In response to the aforementioned request, the higher layer is instructed to provide an intermediate request, which corresponds to a request to the higher layer to cause the UE to transmit SL-PRS to the RX UE in accordance with the aforementioned request. In response to the signal from the upper layer, the RX UE is instructed to transmit SL-PRS on the resources of the dedicated resource pool. UE is structured in such a way.

22. The UE according to claim 21, wherein the upper layer includes a network device implementing the Sidelink Positioning Protocol (SPP), New Radio Positioning Protocol A (NRPPPa), or Long-Term Evolution (LTE) Positioning Protocol (LPP).

23. A user device (UE) comprising memory and a baseband processor, wherein the baseband processor executes instructions stored in the memory, The sidelink positioning reference signal (SL-PRS) transmission power is determined based on the sidelink (SL) path loss between the UE and the receiving (RX) UE or the downlink (DL) path loss between the UE and the receiving (RX) UE. The SL-PRS is transmitted based on the determined SL-PRS transmission power. UE is structured in such a way.

24. The UE according to claim 23, wherein the baseband processor is configured to determine the SL-PRS transmit power based on the SL path loss, the SL path loss is determined based on a reference signal received power (RSRP) measurement received from the RX UE on resources in a shared resource pool linked to a dedicated resource pool configured for the UE for SL-PRS.

25. The baseband processor described above is The UE is configured to receive filtered RSRP values, and the SL-PRS transmission power is based on the filtered RSRP values. The UE according to claim 23.

26. The UE according to claim 25, wherein the baseband processor is configured to cause the UE to transmit to the RX UE a single-stage SCI indicating the reference signal transmission power of a reference signal to be transmitted to the RX UE for use by the RX in calculating the SL path loss.

27. A user device (UE) comprising memory and a baseband processor, wherein the baseband processor executes instructions stored in the memory, It transmits a side-link positioning reference signal (SL-PRS), Transmits an instruction for the transmission time of the SL-PRS or a timestamp associated with the SL-PRS. UE is structured in such a way.

28. The UE according to claim 27, wherein the transmission time or timestamp is reported based on time domain units (Tc), and the quantization of Tc is configured or preconfigured for all resource pools or for each resource pool.

29. The transmission time or timestamp reports the absolute time duration corresponding to the subframe or frame, and the quantization of Tc is fixed, or The transmission time or timestamp is reported as an absolute time duration corresponding to the slot base, and the quantization of Tc is determined based on the subcarrier interval. The UE according to claim 28.

30. The UE according to claim 29, wherein the absolute time duration is 1 millisecond and is in the range of -0.5 milliseconds to 0.5 milliseconds.

31. The UE according to claim 27, wherein the baseband processor is configured to report the SL-PRS transmission time based on a timestamp associated with an OFDM symbol for the start of the SL-PRS transmission or measurement.

Images