Method and apparatus for discontinuous reception operations of sidelink groupcast/broadcast
Methods and apparatuses in a wireless communication system. A method of operating a first UE includes: determining whether to initiate a SL DRX operation for a SL groupcast/broadcast operation; identifying at least one of a SL DRX cycle length, a SL DRX start offset, and SL DRX timers for the SL groupcast/broadcast operation; identifying, based on at least one of a destination ID and the SL DRX start offset, a time instance in which a SL DRX cycle starts, wherein the time instance comprises at least one of a slot, a subframe, and a frame; and receiving, from a second UE belongs to the destination ID, a PSCCH and a PSSCH based on the at least one of the SL DRX cycle length, the SL DRX start offset, the destination ID, and the SL DRX timers.
1. A first user equipment (UE) comprising:
a processor configured to:
identify a layer 2 (L2) destination identification (ID),
determine whether to initiate a sidelink discontinuous (SL DRX) operation for a SL groupcast/broadcast operation, and
determine a SL DRX start offset based on the L2 destination ID; and
a transceiver operably coupled to the processor, the transceiver configured to receive, from a second UE that belongs to the L2 destination ID, a physical sidelink control channel (PSCCH) and a physical sidelink shared channel (PSSCH) based the SL DRX start offset.
2. The first UE of claim 1 , wherein the processor is further configured to determine whether to initiate the SL DRX operation for the SL groupcast/broadcast operation based on the L2 destination ID and information included in pre-configuration information.
3. The first UE of claim 1 , wherein the processor is further configured to:
identify the SL DRX start offset for the SL groupcast/broadcast operation based on pre-configuration information; or
identify the SL DRX start offset for the SL groupcast/broadcast operation based on at least one of a system information block (SIB) or a dedicated radio resource control (RRC) signaling.
4. The first UE of claim 1 , wherein the processor is further configured to:
determine whether a default value is applied for the SL DRX start offset based on characteristics of data transmissions;
apply the default value for the SL DRX start offset based on a determination that the default value is applied; and
apply a first value for the SL DRX start offset based on a determination that the default value is not applied, the default value and the first value are different values from each other.
5. The first UE of claim 1 , wherein:
the processor is further configured to:
determine SL DRX timers for the SL groupcast/broadcast operation, wherein the SL DRX timers comprise values, respectively, and wherein the SL DRX timers are at least one of SL DRX on-duration timers and SL DRX inactivity timers,
determine whether a number of group member UEs is identified by an upper layer of the first UE, and
adjust at least one of the values of the SL DRX timers using a number of scaling factors based on the number of group member Ues.
6. The first UE of claim 5 , wherein the number of scaling factors corresponding to the number of group member Ues is configured based on at least one of pre-configuration information, a system information block (SIB), a dedicated radio resource control (RRC) signaling, or pre-determined values.
7. The first UE of claim 1 , wherein the transceiver is further configured to receive sidelink control information (SCI) or a MAC control element (CE) including an indicator indicating whether the SL DRX operation is applied for the SL groupcast/broadcast operation with the L2 destination ID.
8. A method of a first user equipment (UE), the method comprising:
identifying a layer 2 (L2) destination identification (ID);
determining whether to initiate a sidelink discontinuous (SL DRX) operation for a SL groupcast/broadcast operation;
determining a SL DRX start offset based on the L2 destination ID; and
receiving, from a second UE that belongs to the L2 destination ID, a physical sidelink control channel (PSCCH) and a physical sidelink shared channel (PSSCH) based on the SL DRX start offset.
9. The method of claim 8 , further comprising determining whether to initiate the SL DRX operation for the SL groupcast/broadcast operation based on the L2 destination ID and information included in pre-configuration information.
10. The method of claim 8 , further comprising:
identifying the SL DRX start offset for the SL groupcast/broadcast operation based on pre-configuration information; or
identifying the SL DRX start offset for the SL groupcast/broadcast operation based on at least one of a system information block (SIB) or a dedicated radio resource control (RRC) signaling.
11. The method of claim 8 , further comprising:
determining whether a default value is applied the SL DRX start offset based on characteristics of data transmissions;
applying the default value for the SL DRX start offset based on a determination that the default value is applied; and
applying a first value for the SL DRX start offset based on a determination that the default value is not applied, the default value and the first value are different values from each other.
12. The method of claim 8 , further comprising:
determining SL DRX timers for the SL groupcast/broadcast operation, wherein the SL DRX timers comprise values, respectively, and wherein the SL DRX timers are at least one of SL DRX on-duration timers and SL DRX inactivity timers,
determining whether a number of group member UEs is identified by an upper layer of the first UE; and
adjusting at least one of the values of the SL DRX timers using a number of scaling factors based on the number of group member UEs.
13. The method of claim 12 , wherein the number of scaling factors corresponding to the number of group member UEs is configured based on at least one of pre-configuration information, a system information block (SIB), a dedicated radio resource control (RRC) signaling, or pre-determined values.
14. The method of claim 8 , further comprising receiving sidelink control information (SCI) or a MAC control element (CE) including an indicator indicating whether the SL DRX operation is applied for the SL groupcast/broadcast operation with the L2 destination ID.
15. A second user equipment (UE) comprising:
a processor configured to:
identify a layer 2 (L2) destination identification (ID),
determine whether to initiate a sidelink discontinuous (SL DRX) operation for a SL groupcast/broadcast operation, and
determine a SL DRX start offset based on the L2 destination ID; and
a transceiver operably coupled to the processor, the transceiver configured to transmit, to a first UE that belongs to the L2 destination ID, a physical sidelink control channel (PSCCH) and a physical sidelink shared channel (PSSCH) based on the SL DRX start offset.
16. The second UE of claim 15 , wherein the processor is further configured to determine whether to initiate the SL DRX operation for the SL groupcast/broadcast operation based on the L2 destination ID and information included in pre-configuration information.
17. The second UE of claim 15 , wherein the processor is further configured to:
identify the SL DRX start offset for the SL groupcast/broadcast operation based on pre-configuration information; or
identify the SL DRX start offset for the SL groupcast/broadcast operation based on at least one of a system information block (SIB) or a dedicated radio resource control (RRC) signaling.
18. The second UE of claim 15 , wherein the processor is further configured to:
determine whether a default value is applied for the SL DRX start offset based on characteristics of data transmissions;
apply the default value for the SL DRX start offset based on a determination that the default value is applied; and
apply a first value for the SL DRX start offset based on a determination that the default value is not applied, the default value and the first value are different values from each other.
19. The second UE of claim 15 , wherein:
the processor is further configured to:
determine SL DRX timers for the SL groupcast/broadcast operation, wherein the SL DRX timers comprise values, respectively, and wherein the SL DRX timers are at least one of SL DRX on-duration timers and SL DRX inactivity timers,
determine whether a number of group member UEs is identified by an upper layer of the first UE, and
adjust at least one of the values of the SL DRX timers using a number of scaling factors based on the number of group member UEs; and
the number of scaling factors corresponding to the number of group member UEs is configured based on at least one of pre-configuration information, a system information block (SIB), a dedicated radio resource control (RRC) signaling, or pre-determined values.
20. The second UE of claim 15 , wherein the transceiver is further configured to transmit sidelink control information (SCI) or a MAC control element (CE) including an indicator indicating whether the SL DRX operation is applied for the SL groupcast/broadcast operation with the L2 destination ID.