Discontinuous downlink channel monitoring
Methods, systems, and devices for wireless communications are described. A communication device, otherwise known as a user equipment (UE) may transmit capability information including an indication of a discontinuous monitoring delay period. The UE may receive a message including an indication to adjust monitoring of a physical downlink control channel (PDCCH), and monitor for the PDCCH during the discontinuous monitoring delay period. The UE may adjust monitoring for the PDCCH following the discontinuous monitoring delay period during a temporal period based on the received indication to adjust monitoring of the PDCCH. In some examples, at least one of physical downlink shared channel (PDSCH) reception, downlink reference signal monitoring, uplink reference signal transmissions, and channel reporting is enabled during the temporal period while monitoring of the PDCCH is adjusted.
1. An apparatus for wireless communications at a user equipment (UE), comprising:
one or more memories storing processor-executable code; and
one or more processors coupled with the one or more memories, wherein the one or more processors are individually or collectively configured to cause the UE to:
transmit acknowledgment feedback for a last transport block of a burst of transport blocks;
reduce a retransmission timer at the UE based at least in part on a timing of the last transport block with respect to a beginning of an inactive period for the UE;
monitor for a physical downlink control channel based at least in part on the reduced retransmission timer; and
enter a sleep mode based at least in part on the monitoring, the reduced retransmission timer, and the inactive period for the UE.
2. The apparatus of claim 1 , wherein the one or more processors are individually or collectively further configured to cause the UE to:
enable the reduced retransmission timer over a discontinuous reception cycle.
3. The apparatus of claim 1 , wherein the one or more processors are individually or collectively further configured to cause the UE to:
receive a message comprising an indication of a value of the retransmission timer, wherein reducing the retransmission timer is based at least in part on the value of the retransmission timer in the received message.
4. The apparatus of claim 3 , wherein the one or more processors are individually or collectively further configured to cause the UE to:
remove an offset from the value of the retransmission timer based at least in part on the received message, wherein reducing the retransmission timer is based at least in part on removing the offset from the value of the retransmission timer.
5. The apparatus of claim 3 , wherein the one or more processors are individually or collectively further configured to cause the UE to:
apply a scaling factor to the value of the retransmission timer based at least in part on the received message, wherein reducing the retransmission timer is based at least in part on applying the scaling factor to the value of the retransmission timer.
6. The apparatus of claim 3 , wherein the message comprises a radio resource control message and a downlink control information message scheduling a physical downlink shared channel carrying the last transport block of the burst of transport blocks.
7. The apparatus of claim 1 , wherein the one or more processors are individually or collectively further configured to cause the UE to:
monitor the physical downlink control channel while the retransmission timer is running.
8. The apparatus of claim 7 , wherein the one or more processors are individually or collectively further configured to cause the UE to:
receive a message comprising a bitmap identifying a set of candidate durations for monitoring the physical downlink control channel for candidate retransmissions of the last transport block of the burst of transport blocks, wherein reducing the retransmission timer is based at least in part on the bitmap in the received message.
9. The apparatus of claim 8 , wherein, to monitor the physical downlink control channel, the one or more processors are individually or collectively further configured to cause the UE to:
monitor for the physical downlink control channel to receive the last transport block during a portion of a duration associated with the reduced retransmission timer.
10. The apparatus of claim 1 , wherein the one or more processors are individually or collectively further configured to cause the UE to:
receive a second physical downlink control channel scheduling a retransmission of the last transport block of the burst of transport blocks during a portion of a duration associated with the reduced retransmission timer, wherein the portion is based at least in part on a relationship between a first time associated with the physical downlink control channel scheduling the last transport block and a second time of a transmission of the last transport block or a third time of the transmitted acknowledgment feedback for the last transport block; and
receive the retransmission of the last transport block of the burst of transport blocks.
11. The apparatus of claim 1 , wherein, to transmit the acknowledgement feedback, the one or more processors are individually or collectively further configured to cause the UE to:
transmit a hybrid automatic repeat request feedback message based at least in part on receiving the burst of transport blocks during an active portion of a discontinuous reception cycle; and
deactivate the reduced retransmission timer based at least in part on transmitting the hybrid automatic repeat request feedback message.
12. The apparatus of claim 1 , wherein, to transmit the acknowledgement feedback, the one or more processors are individually or collectively further configured to cause the UE to:
transmit a positive hybrid automatic repeat request feedback message based at least in part on receiving a retransmission of the last transport block of the burst of transport blocks during a portion of a duration associated with the reduced retransmission timer; and
deactivate the reduced retransmission timer based at least in part on transmitting the hybrid automatic repeat request feedback message.
13. The apparatus of claim 1 , wherein the one or more processors are individually or collectively further configured to cause the UE to:
receive a message comprising an indication to deactivate a group of search space sets associated with an active portion of a discontinuous reception cycle based at least in part on a grant for the last transport block of the burst of transport blocks; and
deactivate the group of search space sets based at least in part on the received message.
14. The apparatus of claim 1 , wherein the one or more processors are individually or collectively further configured to cause the UE to:
transmit a negative hybrid automatic repeat request feedback message for the last transport block of the burst of transport blocks based at least in part on the UE failing to receive the last transport block of the burst of transport blocks; and
activate a group of search space sets associated with retransmission of the last transport block of the burst of transport blocks based at least in part on the transmitted negative hybrid automatic repeat request feedback message, wherein the group of search space sets corresponds to an active portion of a discontinuous reception cycle.
15. An apparatus for wireless communications at a network entity, comprising:
one or more memories storing processor-executable code; and
one or more processors coupled with the one or more memories, wherein the one or more processors are individually or collectively configured to cause the network entity to:
transmit a last transport block of a burst of transport blocks to a user equipment (UE);
receive acknowledgment feedback for the last transport block of the burst of transport blocks; and
retransmit the last transport block scheduled by a physical downlink control channel during a portion of a duration associated with a reduced retransmission timer, wherein the reduced retransmission timer is based at least in part on a timing of the last transport block with respect to a beginning of an inactive period for the UE.
16. The apparatus of claim 15 , wherein the one or more processors are individually or collectively further configured to cause the network entity to:
transmit a message comprising an indication of a value of the retransmission timer, wherein the message comprises a radio resource control message and a downlink control information message scheduling the physical downlink control channel carrying the last transport block of the burst of transport blocks.
17. The apparatus of claim 15 , wherein the one or more processors are individually or collectively further configured to cause the network entity to:
transmit a message comprising a bitmap identifying a set of candidate durations for physical downlink control channel scheduling candidate retransmissions of the last transport block of the burst of transport blocks.
18. The apparatus of claim 15 , wherein, to retransmit the last transport block, the one or more processors are individually or collectively further configured to cause the network entity to:
transmit the retransmission of the last transport block of the burst of transport blocks.
19. The apparatus of claim 18 , wherein the portion is based at least in part on a relationship between a first time associated with the transmitting physical downlink control channel scheduling the last transport block and a second time of a transmission of the last transport block or a third time of the transmitted acknowledgment feedback for the last transport block by the UE.
20. The apparatus of claim 15 , wherein, to receive acknowledgment feedback, wherein the one or more processors are individually or collectively further configured to cause the network entity to:
receive a hybrid automatic repeat request feedback message based at least in part on retransmitting the last transport block during an active portion of a discontinuous reception cycle.
21. The apparatus of claim 15 , wherein the one or more processors are individually or collectively further configured to cause the network entity to:
allocate a grant for the last transport block of the burst of transport blocks; and
transmit a message comprising an indication to deactivate a group of search space sets associated with an active portion of a discontinuous reception cycle based at least in part on the grant for the last transport block of the burst of transport blocks.
22. A method for wireless communication at a user equipment (UE), comprising:
transmitting acknowledgment feedback for a last transport block of a burst of transport blocks;
reducing a retransmission timer at the UE based at least in part on a timing of the last transport block with respect to a beginning of an inactive period for the UE;
monitoring for a physical downlink control channel based at least in part on the reduced retransmission timer; and
entering a sleep mode based at least in part on the monitoring, the reduced retransmission timer, and the inactive period for the UE.
23. The method of claim 22 , further comprising:
enabling the reduced retransmission timer over a discontinuous reception cycle.
24. The method of claim 22 , further comprising:
receiving a message comprising an indication of a value of the retransmission timer, wherein reducing the retransmission timer is based at least in part on the value of the retransmission timer in the received message.
25. The method of claim 22 , further comprising:
monitoring the physical downlink control channel while the retransmission timer is running.
26. The method of claim 22 , further comprising:
receiving a second physical downlink control channel scheduling a retransmission of the last transport block of the burst of transport blocks during a portion of a duration associated with the reduced retransmission timer, wherein the portion is based at least in part on a relationship between a first time associated with the physical downlink control channel scheduling the last transport block and a second time of a transmission of the last transport block or a third time of the transmitted acknowledgment feedback for the last transport block; and
receive the retransmission of the last transport block of the burst of transport blocks.
27. The method of claim 22 , transmitting the acknowledgement feedback comprises:
transmitting a hybrid automatic repeat request feedback message based at least in part on receiving the burst of transport blocks during an active portion of a discontinuous reception cycle; and
deactivating the reduced retransmission timer based at least in part on transmitting the hybrid automatic repeat request feedback message.
28. The method of claim 22 , wherein, to transmitting the acknowledgement feedback comprises:
transmitting a positive hybrid automatic repeat request feedback message based at least in part on receiving a retransmission of the last transport block of the burst of transport blocks during a portion of a duration associated with the reduced retransmission timer; and
deactivating the reduced retransmission timer based at least in part on transmitting the hybrid automatic repeat request feedback message.
29. The method of claim 22 , further comprising:
receiving a message comprising an indication to deactivate a group of search space sets associated with an active portion of a discontinuous reception cycle based at least in part on a grant for the last transport block of the burst of transport blocks; and
deactivating the group of search space sets based at least in part on the received message.
30. The method of claim 22 , further comprising:
transmitting a negative hybrid automatic repeat request feedback message for the last transport block of the burst of transport blocks based at least in part on the UE failing to receive the last transport block of the burst of transport blocks; and
activating a group of search space sets associated with retransmission of the last transport block of the burst of transport blocks based at least in part on the transmitted negative hybrid automatic repeat request feedback message, wherein the group of search space sets corresponds to an active portion of a discontinuous reception cycle.