Search

EP-4740348-A1 - SIDELINK POSITIONING REFERENCE SIGNALS

EP4740348A1EP 4740348 A1EP4740348 A1EP 4740348A1EP-4740348-A1

Abstract

Systems, methods, and devices are provided for transmitting and receiving sidelink positioning reference signals (SL-PRS). In one example, a user equipment (UE), includes a memory and a baseband processor. The baseband processor is configured to, when executing instructions stored in the memory, cause the UE to select a sidelink positioning reference signal (SL-PRS) resource from a configured or preconfigured 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, wherein the dedicated resource pool does not include candidate resources for physical sidelink shared channel (PSSCH) transmission. The baseband processor is configured to cause the UE to transmit the SL-PRS in the selected SL-PRS resource.

Inventors

  • YE, CHUNXUAN
  • ZHANG, DAWEI
  • OTERI, OGHENEKOME
  • YANG, WEIDONG
  • ZENG, WEI
  • SUN, HAITONG
  • HE, HONG

Assignees

  • Apple Inc.

Dates

Publication Date
20260513
Application Date
20230811

Claims (20)

  1. 1. A user equipment (UE), comprising: a memory; and a baseband processor configured to, when executing instructions stored in the memory, cause the UE to select a sidelink positioning reference signal (SL-PRS) resource from a dedicated resource pool, wherein 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, wherein the dedicated resource pool does not include candidate resources for physical sidelink shared channel (PSSCH) transmission; and transmit the SL-PRS in the selected SL-PRS resource.
  2. 2. The UE of claim 1, wherein each candidate SL-PRS resource is indicated by a slot index and a sub-channel index or a slot index and an SL-PRS resource index.
  3. 3. The UE of claim 2, wherein PSCCH resources in slot in the dedicated resource pool are indexed in terms of frequency location; and SL-PRS resources in a slot in the dedicated resource pool are indexed in order of frequency in an SL-PRS resource first, and by SL-PRS resource second; or in order of symbol in an SL-PRS resource first, frequency in an SL-RS resource second, and SL-PRS resource third; or in order of symbol in an SL-PRS resource first, SL-PRS resource second, and frequency third.
  4. 4. The UE of claim 2, wherein each PSCCH resource is mapped to one SL-PRS resource, where a mapped SL-PRS resource index is the same as a PSCCH resource index or the mapped SL-PRS resource index is different from the PSCCH resource index.
  5. 5. The UE of claim 2, wherein each PSCCH is mapped to a set of SL-PRS resources and wherein the baseband processor is configured to transmit an indication of a selected one of the set of SL-PRS resource in single stage SCI carried by the PSCCH resource.
  6. 6. The UE of claim 1, wherein the baseband processor is configured to cause the UE to select the SL-PRS resource from the dedicated resource pool by measuring a reference signal receive power (RSRP) of single stage SCI in candidate PSCCH of the dedicated resource pool; decoding the single stage SCI to determine a resource reservation period and priority of respective SL-PRS associated with respective SCI; and excluding, from the candidate resource pool, candidate resources associated with single stage SCI having a higher RSRP than a threshold.
  7. 7. The UE of claim 6, wherein the threshold is selected based on the priority indicated in the single stage SCI or a priority of the SL-PRS.
  8. 8. The UE of claim 1, wherein the single stage SCI includes an indication of one or more of a source ID for the UE, a destination ID for a receive (RX) UE, a priority of an associated SL- PRS, a resource reservation period, an aperiodic resource reservation, an SL-PRS resource indicator for a first transmission, an SL-PRS resource indicator for a re-transmission of the SL- PRS, a PHY layer reference signal receive power (RSRP) report, or a an RRC layer RSRP report.
  9. 9. A user equipment (UE), comprising: a memory; and a baseband processor configured to, when executing instructions stored in the memory, cause the UE to select a sidelink positioning reference signal (SL-PRS) resource based on a resource allocation received from a network; and transmit the SL-PRS in the selected SL-PRS resource.
  10. 10. The UE of claim 9, wherein the resource allocation comprises 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 assigned to the UE based on a dedicated resource pool.
  11. 11. The UE of claim 9, wherein the resource allocation comprises a configured grant that indicates one or more of an SL-PRS configured grant configuration index, an SL-PRS configured grant period, a time resource of the configured grant, a time offset of the configured grant, a time reference system frame number of the SL-PRS, a dedicated resource pool identifier.
  12. 12. A user equipment (UE), comprising memory and a baseband processor configured to, when executing instructions stored in the memory, cause the UE to exchange unicast messages with a second UE using resources of a shared resource pool; and transmit or receive sidelink positioning reference signals (SL-PRS) using SL-PRS resources of a dedicated resource pool, wherein the dedicated resource pool is linked to the shared resource pool by configuration or pre-configuration.
  13. 13. The UE of claim 12, wherein the baseband processor is configured to cause the UE to establish a unicast link with the second UE using resources of the shared resource pool; receive a destination identifier (ID) or a source ID from the second UE using resources of the shared resource pool; and transmitting or receiving SL-PRS based on the received destination ID or source ID.
  14. 14. The UE of claim 13, wherein the baseband processor is configured to cause the UE to transmit or receive an UE capability information or an open loop power configuration using the unicast link.
  15. 15. A user equipment (UE), comprising memory and a baseband processor configured to, when executing instructions stored in the memory, cause the UE to determine a MAC layer destination ID of a transmit (TX) UE; derive a PHY layer destination ID based on the MAC layer destination ID; transmit a PHY layer request to the TX UE for a sidelink positioning reference signal (SL-PRS); and receive SL-PRS on resources of a dedicated resource pool from the TX UE.
  16. 16. The UE of claim 15, wherein the baseband processor is configured to determine the MAC destination ID by establishing a unicast link with TX UE using a shared resource pool that is linked to the dedicated resource pool, wherein the UE i configured or preconfigured with the shared resource pool or the dedicated resource pool; and determining the MAC layer destination ID based on the unicast link.
  17. 17. The UE of claim 16, wherein the baseband processor is configured to determine a MAC layer source ID based on either the dedicated resource pool or the shared resource pool.
  18. 18. The UE of claim 15, 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 preconfiguration or by the UE.
  19. 19. The UE of claim 15, wherein the baseband processor is configured to determine the MAC layer destination ID based on preconfiguration of the dedicated resource pool, signaling from a network configuring the dedicated resource pool, or a policy control function (PCF).
  20. 20. The UE of claim 15, wherein the baseband processor is configured to cause the UE to transmit sidelink control information (SCI) that includes the request for SL-PRS.

Description

SIDELINK POSITIONING REFERENCE SIGNALS BACKGROUND [0001] The present disclosure relates generally to wireless communication and more specifically to techniques for performing sidelink or device-to- device communication in a radio network. BRIEF DESCRIPTION OF THE DRAWINGS [0002] Some examples of circuits, apparatuses and/or methods will be described in the following by way of example only. In this context, reference will be made to the accompanying figures. [0003] FIG. 1 is a diagram of an example downlink (DL) position reference signal (PRS), in accordance with various aspects described. [0004] FIG. 2 is a diagram of an example sidelink shared resource pool, in accordance with various aspects described. [0005] FIG. 3 illustrates an example slot configuration for a sidelink physical sidelink control channel/physical sidelink shared channel (PSCCH/PSSCH) slot, in accordance with various aspects described. [0006] FIG. 4 illustrates sidelink communication being performed in mode 1 or mode 2, in accordance with various aspects described. [0007] FIG. 5 illustrates an example sidelink shared resource pool, in accordance with various aspects described. [0008] FIG. 6 illustrates an example sidelink dedicated resource pool, in accordance with various aspects described. [0009] FIGs. 7A and 7B illustrate example SL-PRS resources and different SL-PRS resource indexing ordering conventions, in accordance with various aspects described. [0010] FIG. 8 is a table indicating a value for k’ used in SL-PRS sequence mapping, in accordance with various aspects described. [0011] FIGs. 9A,9B,9C,9D illustrate different example mappings between PSCCH and sidelink positioning reference signal (SL-PRs) resources, in accordance with various aspects described. [0012] FIG. 10 is a flow diagram outlining an example method for transmitting SL-PRS, in accordance with various aspects described. [0013] FIG. 11 is a message flow diagram outlining an SL-PRS transmission process, in accordance with various aspects disclosed. [0014] FIG. 12 is a flow diagram outlining an example method for transmitting SL-PRS using resources from a dedicated resource pool, in accordance with various aspects described. [0015] FIG. 13 is a flow diagram outlining an example method for transmitting SL-PRS based on an allocation from a network, in accordance with various aspects described. [0016] FIG. 14 is a flow diagram outlining an example method for configuring transmission of SL-PRS using resources from a shared dedicated resource pool that is linked to a dedicated resource pool, in accordance with various aspects described. [0017] FIG. 15 is a flow diagram outlining an example method for requesting SL-PRS from a UE with which a unicast link has not been established, in accordance with various aspects described. [0018] FIG. 16 is a flow diagram outlining an example method for transmitting SL-PRS based on configuration from a higher layer, in accordance with various aspects described. [0019] FIG. 17 is a flow diagram outlining an example method for determining SL-PRS transmit power based on sidelink pathloss, in accordance with various aspects described. [0020] FIG. 18 is a flow diagram outlining an example method for transmitting an indication of a transmission time of an SL-PRS, in accordance with various aspects described. [0021] FIG. 19 is a functional block diagram of a wireless communication network, in accordance with various aspects described. [0022] FIG. 20 illustrates a simplified block diagram of a user equipment device, in accordance with various aspects described. DETAILED DESCRIPTION [0023] The present disclosure is described with reference to the attached figures. The figures are not drawn to scale and they are provided merely to illustrate the disclosure. Several aspects of the disclosure are described below with reference to example applications for illustration. Numerous specific details, relationships, and methods are set forth to provide an understanding of the disclosure. The present disclosure is not limited by the illustrated ordering of acts or events, as some acts may occur in different orders and/or concurrently with other acts or events. Furthermore, not all illustrated acts or events are required to implement a methodology in accordance with the selected present disclosure. [0024] In many instances, a mobile communication device, such as a user equipment (UE), performs actions based on the device’s position. Obvious examples include navigation applications and internet searches that seek results based on proximity to the device. To assist UEs in determining their position, base stations and access points transmit positioning reference signals (PRS) that may be received and measured by a UE for use in determining the UE’s position. In uplink (UL), UEs transmit sounding reference signals (SRS) that may be received and measured by a base station or access point. The base station or access point may transmit measurement values for the