Methods and apparatus for combined signaling for sidelink assisted positioning
Positioning of one or more user equipments (UEs) is performed using broadcast common sounding reference signals (SRS) resources for positioning. The common SRS that is broadcast by a UE is received and measured by one or more base stations and one or more other UEs. The other UEs may have known positions and may server as anchor nodes for positioning. The other UEs may have known positions and may serve as a positioning (anchor) node or may have unknown positions and may be jointly positioned with the target UE. During joint positioning, each of the other UEs may similarly broadcast a common set of SRS that is received and measured by the base stations and other UEs for positioning. An angular measurement of the SRS broadcast by one or more UEs may be measured and used to resolve minor symmetry in positioning solutions.
1. An apparatus for wireless communication at a user equipment (UE) for supporting positioning of a target UE, comprising:
at least one memory; and
at least one processor coupled to the at least one memory and, based at least in part on information stored in the at least one memory, the at least one processor, individually or in any combination, is configured to:
receive a sounding reference signal (SRS) configuration associated with a first common SRS resource for positioning;
receive the first common SRS resource from the target UE based on the SRS configuration; and
transmit a second common SRS resource in response to the reception of the first common SRS resource from the target UE,
wherein, to receive the SRS configuration associated with the first common SRS resource, the at least one processor, individually or in any combination, is configured to:
receive assistance data for the first common SRS resource, and wherein, to receive the first common SRS resource from the target UE, the at least one processor, individually or in any combination, is configured to receive the first common SRS resource based on the assistance data.
2. The apparatus of claim 1 , wherein the at least one processor, individually or in any combination, is further configured to:
measure a first positioning measurement based on the first common SRS resource; and
transmit a report comprising an indicator of the first positioning measurement to a positioning entity.
3. The apparatus of claim 2 , wherein the positioning entity calculates a position of the target UE based on the report and the second common SRS resource.
4. The apparatus of claim 2 , wherein the positioning entity comprises a location server, a base station, or the target UE.
5. The apparatus of claim 1 , wherein the at least one processor, individually or in any combination, is further configured to:
transmit a report comprising an indicator of a reception transmission (Rx-Tx) time difference associated with the transmission of the second common SRS resource.
6. The apparatus of claim 1 , wherein the first common SRS resource comprises a sidelink (SL) signal.
7. The apparatus of claim 1 , wherein the second common SRS resource comprises an uplink (UL) signal.
8. The apparatus of claim 1 , wherein the second common SRS resource comprises a sidelink (SL) signal.
9. The apparatus of claim 1 , wherein, to transmit the second common SRS resource, the at least one processor, individually or in any combination, is configured to:
transmit the second common SRS resource to at least one of a base station or the target UE.
10. The apparatus of claim 9 , wherein the base station measures a first positioning measurement based on the first common SRS resource and measures a second positioning measurement based on the second common SRS resource, wherein at least one of the base station or a positioning entity calculates a position of the target UE based on the first positioning measurement and the second positioning measurement.
11. The apparatus of claim 1 , further comprising a transceiver coupled to the at least one processor, wherein the at least one processor, individually or in any combination, is further configured to:
receive, via the transceiver, the SRS configuration;
receive, via the transceiver, the first common SRS resource from the target UE based on the SRS configuration; and
transmit, via the transceiver, the second common SRS resource in response to the reception of the first common SRS resource from the target UE.
12. An apparatus for wireless communication at a base station for supporting positioning of a target UE, comprising:
at least one memory; and
at least one processor coupled to the at least one memory and, based at least in part on information stored in the at least one memory, the at least one processor, individually or in any combination, is configured to:
receive a first sounding reference signal (SRS) configuration associated with a first common SRS resource for positioning and a second SRS configuration associated with a second common SRS resource for positioning;
receive the first common SRS resource from the target UE based on the first SRS configuration;
measure a first positioning measurement based on the first common SRS resource;
receive the second common SRS resource from an assisting UE based on the second SRS configuration; and
measure a second positioning measurement based on the second common SRS resource.
13. The apparatus of claim 12 , wherein the at least one processor, individually or in any combination, is further configured to:
calculate a position of the target UE based on the first positioning measurement and the second positioning measurement.
14. The apparatus of claim 13 , wherein a second position of the assisting UE is known, wherein, to calculate the position of the target UE, the at least one processor, individually or in any combination, is further configured to calculate the position of the target UE based on the second position of the assisting UE.
15. The apparatus of claim 13 , wherein a second position of the assisting UE is unknown, wherein, the at least one processor, individually or in any combination, is further configured to:
calculate the second position of the assisting UE based on the second positioning measurement, wherein, to calculate the position of the target UE, the at least one processor, individually or in any combination, is further configured to calculate the position of the target UE based on the second position of the assisting UE.
16. The apparatus of claim 12 , wherein the at least one processor, individually or in any combination, is further configured to:
transmit a report comprising a first indicator of the first positioning measurement and a second indicator of the second positioning measurement to a positioning entity.
17. The apparatus of claim 16 , wherein the positioning entity calculates a position of the target UE based on the first positioning measurement and the second positioning measurement.
18. A method for wireless communication at a user equipment (UE) for supporting positioning of a target UE, comprising:
receiving a sounding reference signal (SRS) configuration associated with a first common SRS resource for positioning;
receiving the first common SRS resource from the target UE based on the SRS configuration; and
transmitting a second common SRS resource in response to the reception of the first common SRS resource from the target UE,
wherein, receiving the SRS configuration associated with the first common SRS resource comprises receiving assistance data for the first common SRS resource, and wherein receiving the first common SRS resource from the target UE comprises receiving the first common SRS resource based on the assistance data.