Discontinuous reception (DRX) based anchor user equipment (UE) selection for joint positioning sessions

1 . A method of wireless positioning performed by a user equipment (UE) operating in discontinuous reception (DRX) mode, comprising:

receiving an anchor selection update message from a location server, the anchor selection update message indicating that the UE has been selected as an anchor UE for a joint positioning session with one or more second UEs, wherein the UE is selected as the anchor UE based at least in part on the UE having DRX active time occasions closer to a plurality of measurement occasions for the joint positioning session than DRX active time occasions of the one or more second UEs;

performing, in response to reception of the anchor selection update message, positioning measurements for the joint positioning session during one or more measurement occasions of the plurality of measurement occasions that overlap with the DRX active time occasions of the UE; and

transmitting, to the one or more second UEs, the positioning measurements, a location of the UE determined based on the positioning measurements, or both.

2 . The method of claim 1 , further comprising:

transmitting a measurement report to the location server, the measurement report including the positioning measurements; and

receiving a positioning report from the location server, the positioning report including at least the location of the UE.

3 . The method of claim 1 , further comprising:

determining the location of the UE.

4 . The method of claim 1 , wherein the UE is selected as the anchor UE based at least in part on a battery status, a UE type, capabilities, bandwidth part (BWP), or any combination thereof of the UE compared to battery statuses, UE types, capabilities, BWPs, or any combination thereof of the one or more second UEs.

5 . The method of claim 1 , further comprising:

transmitting a request for at least a new DRX cycle length to a base station serving the UE, wherein the new DRX cycle length aligns the DRX active time occasions with the plurality of measurement occasions.

6 . The method of claim 1 , further comprising:

receiving a first DRX configuration from a base station serving the UE, wherein the first DRX configuration is common to second DRX configurations of the one or more second UEs.

7 . The method of claim 6 , wherein the first DRX configuration being common to the second DRX configurations of the one or more second UEs comprises DRX active time occasions of the first DRX configuration at least partially overlapping with DRX active time occasions of the second DRX configurations.

8 . The method of claim 6 , wherein the first DRX configuration includes a Uu DRX configuration and a sidelink DRX configuration.

9 . The method of claim 1 , further comprising:

transmitting a DRX configuration update message to a location server, the DRX configuration update message indicating a DRX configuration of the UE, the DRX configuration indicating the DRX active time occasions for the UE.

10 . The method of claim 9 , further comprising:

receiving a request for the DRX configuration from the location server.

11 . A method of positioning performed by a location server, comprising:

receiving a plurality of discontinuous reception (DRX) configurations for a plurality of user equipments (UEs) engaged in a joint positioning session with each other, each of the plurality of DRX configurations indicating at least DRX active time occasions for the corresponding UE;

selecting one UE of the plurality of UEs to be an anchor UE for the joint positioning session based at least in part on the anchor UE having DRX active time occasions closer to a plurality of measurement occasions for the joint positioning session than DRX active time occasions of remaining UEs of the plurality of UEs; and

transmitting an anchor selection update message to each of the plurality of UEs, the anchor selection update message indicating that the anchor UE has been selected as the anchor UE for the joint positioning session.

12 . The method of claim 11 , wherein:

the plurality of DRX configurations are received from the plurality of UEs, or

the plurality of DRX configurations are received from an access and mobility management function (AMF) serving the plurality of UEs.

13 . The method of claim 11 , further comprising:

receiving a measurement report from the anchor UE, the measurement report including positioning measurements performed by the anchor UE for the joint positioning session;

determining a location of the anchor UE based on the positioning measurements; and

transmitting a positioning report to the anchor UE, the positioning report including at least the location of the anchor UE.

14 . The method of claim 11 , wherein the anchor UE is further selected as the anchor UE based at least in part on a battery status, a UE type, capabilities, bandwidth part (BWP), or any combination thereof of the anchor UE compared to battery statuses, UE types, capabilities, BWPs, or any combination thereof of remaining UEs of the plurality of UEs.

15 . The method of claim 11 , further comprising:

transmitting a request for at least a new DRX cycle length for the anchor UE, wherein the new DRX cycle length aligns the DRX active time occasions of the anchor UE with the plurality of measurement occasions.

16 . The method of claim 15 , wherein the request is transmitted to:

a serving base station of the anchor UE, or

an AMF serving the anchor UE.

17 . The method of claim 11 , further comprising:

transmitting, to an AMF serving the plurality of UEs, a recommendation to group the plurality of UEs into a DRX group and to configure all of the plurality of UEs with a common DRX configuration; and

transmitting, to the AMF, recommended DRX parameters for the common DRX configuration, wherein the recommended DRX parameters at least partially overlaps DRX active time occasions of the plurality of UEs with the plurality of measurement occasions.

18 . The method of claim 17 , wherein the common DRX configuration includes a Uu DRX configuration and a sidelink DRX configuration.

19 . The method of claim 11 , further comprising:

receiving a plurality of DRX configuration update messages from the plurality of UEs, the plurality of DRX configuration update messages indicating a plurality of DRX configurations of the plurality of UEs.

20 . The method of claim 19 , further comprising:

transmitting a plurality of requests to the plurality of UEs for the plurality of DRX configurations.

21 . A method of wireless positioning performed by a user equipment (UE) operating in discontinuous reception (DRX) mode, comprising:

receiving an anchor selection update message from a location server, the anchor selection update message indicating that a peer UE has been selected as an anchor UE for a joint positioning session among a plurality of UEs, including the UE and the peer UE, wherein the peer UE is selected as the anchor UE based at least in part on the peer UE having DRX active time occasions closer to a plurality of measurement occasions for the joint positioning session than DRX active time occasions of remaining UEs of the plurality of UEs; and

receiving, from the peer UE, positioning measurements performed by the peer UE for the joint positioning session, a location of the peer UE determined based on the positioning measurements, or both.

22 . The method of claim 21 , further comprising:

adopting the location of the peer UE as a location of the UE.

23 . The method of claim 21 , further comprising:

determining a location of the UE based on the positioning measurements.

24 . The method of claim 21 , further comprising:

transmitting a DRX configuration update message to a location server, the DRX configuration update message indicating a DRX configuration of the UE, the DRX configuration indicating the DRX active time occasions for the UE.

25 . The method of claim 24 , further comprising:

receiving a request for the DRX configuration from the location server.

26 . A user equipment (UE), comprising:

a memory;

at least one transceiver; and

at least one processor communicatively coupled to the memory and the at least one transceiver, the at least one processor configured to:

receive, via the at least one transceiver, an anchor selection update message from a location server, the anchor selection update message indicating that the UE has been selected as an anchor UE for a joint positioning session with one or more second UEs, wherein the UE is selected as the anchor UE based at least in part on the UE having DRX active time occasions closer to a plurality of measurement occasions for the joint positioning session than DRX active time occasions of the one or more second UEs;

perform, in response to reception of the anchor selection update message, positioning measurements for the joint positioning session during one or more measurement occasions of the plurality of measurement occasions that overlap with the DRX active time occasions of the UE; and

transmit, via the at least one transceiver, to the one or more second UEs, the positioning measurements, a location of the UE determined based on the positioning measurements, or both.

27 . The UE of claim 26 , wherein the UE is selected as the anchor UE based at least in part on a battery status, a UE type, capabilities, bandwidth part (BWP), or any combination thereof of the UE compared to battery statuses, UE types, capabilities, BWPs, or any combination thereof of the one or more second UEs.

28 . The UE of claim 26 , wherein the at least one processor is further configured to:

transmit, via the at least one transceiver, a request for at least a new DRX cycle length to a base station serving the UE, wherein the new DRX cycle length aligns the DRX active time occasions with the plurality of measurement occasions.

29 . The UE of claim 26 , wherein the at least one processor is further configured to:

receive, via the at least one transceiver, a first DRX configuration from a base station serving the UE, wherein the first DRX configuration is common to second DRX configurations of the one or more second UEs.

30 . The UE of claim 26 , wherein the at least one processor is further configured to:

transmit, via the at least one transceiver, a DRX configuration update message to a location server, the DRX configuration update message indicating a DRX configuration of the UE, the DRX configuration indicating the DRX active time occasions for the UE.