Joint optimization of bandwidth part, search space and connected mode discontinuous reception operation in 5G New Radio
Apparatuses, systems, and methods for a user equipment device (UE) to perform a method using a status change of a timer associated with a connected mode discontinuous reception (CDRX) communication session with a base station to trigger a switch from using a first bandwidth part (BWP) to a second BWP as the active BWP for the CDRX communication session. The timer may be an on-duration timer, an inactivity timer, or a retransmission timer. The UE may also alter a monitoring schedule of a physical downlink control channel (PDCCH) in response to detecting the status change of the timer. The second BWP may have a wider or narrower bandwidth than the first BWP, depending on the type of timer and the type of status change.
1. A method, comprising:
by a user equipment device (UE):
communicating with a base station using a first bandwidth part (BWP) as an active BWP in a connected mode discontinuous reception (CDRX) communication session;
determining that a first timer has experienced a status change; and
switching a first search space to monitor and a periodicity of monitoring the first search space in the first BWP based at least in part on the determination that the first timer has experienced the status change.
2. The method of claim 1 ,
wherein the first timer is an inactivity timer,
wherein the status change comprises an initiation of the inactivity timer, and
wherein the first search space is switched to a search space with enhanced monitoring parameters.
3. The method of claim 1 ,
wherein the first timer is an inactivity timer,
wherein the status change comprises an expiration of the inactivity timer, and
wherein the first search space is switched to a search space with power saving parameters.
4. The method of claim 3 , the method further comprising:
determining that a retransmission timer is running when the inactivity timer expires, and
wherein switching the first search space to monitor and the periodicity of monitoring the first search space is further based at least in part on the determination that the retransmission timer is running when the inactivity timer expires.
5. The method of claim 1 , the method further comprising:
subsequent to switching the first search space to monitor and the periodicity of monitoring the first search space, determining that a second timer has expired; and
transitioning the UE to a DRX sleep state based at least in part on the determination that the second timer has expired.
6. The method of claim 1 , the method further comprising:
by the UE:
when the first BWP is used as the active BWP, continuously monitoring a physical downlink control channel (PDCCH); and
switching from continuously monitoring the PDCCH to periodically monitoring the PDCCH based at least in part on the determination that the first timer has experienced the status change.
7. The method of claim 1 , the method further comprising:
based at least in part on the determination that the first timer has experienced the status change, switching a control resource set (CORESET) associated with the CDRX communication session.
8. The method of claim 7 ,
wherein switching the CORESET associated with the CDRX communication session comprises switching a monitoring duration of a physical downlink control channel (PDCCH).
9. The method of claim 1 ,
wherein communicating with the base station using the first BWP as the active BWP in the CDRX communication session is performed in response to detection by the UE of initiation of an on-duration timer.
10. The method of claim 1 , the method further comprising:
by the UE:
transmitting an uplink message to the base station and monitoring for a hybrid automatic repeat request (HARD) message associated with the transmitted uplink message while communicating with the base station using the first BWP as the active BWP, wherein said switching the first search space to monitor and the periodicity of monitoring the first search space occurs before the UE receives the HARQ message.
11. The method of claim 1 ,
wherein the first timer experiencing the status change is associated with light traffic of the CDRX communication session, and
wherein the first search space comprises a power saving search space.
12. The method of claim 1 ,
wherein the first timer experiencing the status change is associated with heavy traffic of the CDRX communication session, and
wherein the first search space comprises an enhanced monitoring search space.
13. A user equipment device (UE), comprising:
an antenna;
a radio coupled to the antenna; and
a processing element coupled to the radio;
wherein the UE is configured to:
communicate with a base station using a first bandwidth part (BWP) as an active BWP in a connected mode discontinuous reception (CDRX) communication session;
determine that a first timer has experienced a status change; and
switch a first search space to monitor and a periodicity of monitoring the first search space in the first BWP based at least in part on the determination that the first timer has experienced the status change.
14. The UE of claim 13 ,
wherein the status change of the first timer is associated with light traffic of the CDRX communication session, and
wherein the first search space comprises a power saving search space.
15. The UE of claim 13 ,
wherein the status change of the first timer is associated with heavy traffic of the CDRX communication session, and
wherein the first search space comprises an enhanced monitoring search space.
16. An apparatus, comprising:
a processor configured to cause a user equipment device (UE) to:
communicate with a base station using a first bandwidth part (BWP) as an active BWP in a connected mode discontinuous reception (CDRX) communication session;
determine that a first timer has experienced a status change; and
switch a first search space to monitor and a periodicity of monitoring the first search space in the first BWP based at least in part on the determination that the first timer has experienced the status change.
17. The apparatus of claim 16 , wherein the processor is further configured to cause the UE to:
based at least in part on the determination that the first timer has experienced the status change, switch a control resource set (CORESET) associated with the CDRX communication session,
wherein switching the CORESET associated with the CDRX communication session comprises switching the monitoring duration of a physical downlink control channel (PDCCH).
18. The apparatus of claim 16 ,
wherein the first timer is an inactivity timer,
wherein when the status change comprises an initiation of the inactivity timer, the first search space is switched to a search space with enhanced monitoring parameters, and
wherein when the status change comprises an expiration of the inactivity timer, the first search space is switched to a search space with power saving parameters.
19. The apparatus of claim 16 ,
wherein the first timer experiencing the status change is associated with light traffic of the CDRX communication session, and
wherein the first search space comprises a power saving search space.
20. The apparatus of claim 16 ,
wherein the first timer experiencing the status change is associated with heavy traffic of the CDRX communication session, and
wherein the first search space comprises an enhanced monitoring search space.