Sensing for user equipment (UE) supporting sidelink discontinuous reception (SL-DRX)

Patent metadata

Field	Value
Publication number	US-12349113-B2
Application number	US-202017439772-A
Country	US
Kind code	B2
Filing date	Sep 25, 2020
Priority date	Sep 25, 2020
Publication date	Jul 1, 2025
Grant date	Jul 1, 2025

Abstract

Some embodiments include a system, method, and computer program product for managing power consumption of a user equipment (UE) supporting sidelink discontinuous reception (SL-DRX) in a 5G wireless communications system. A UE determines a candidate slot for sending a signal based on data sensed in various periods over a history window. Some embodiments include a processor that can determine set of candidate slots that are sufficiently sensed based on sensed periods over a history window, and determine a subset of candidate slots of the set of candidate slots based at least on an occupancy threshold over the history window. The processor can select a candidate slot from the subset of candidate slots, and transmit via the transceiver, a first signal via the selected candidate slot.

First claim

What is claimed is:

1. A user equipment (UE) system comprising:
a transceiver; and
a processor coupled to the transceiver, configured to:
determine a set of candidate slots that have been sensed over a plurality of sensed periods of a history window, wherein a sensed period of the plurality of sensed periods corresponds to a sidelink discontinuous reception (SL-DRX) Active Time duration that exceeds an SL-DRX ON Duration, and wherein the plurality of sensed periods is less than a plurality of periods of the history window;
determine a subset of candidate slots from the set of candidate slots based at least on an occupancy threshold;
select a first candidate slot from the subset of candidate slots; and
transmit via the transceiver, a first signal via the first candidate slot.

2. The UE of claim 1 , wherein a plurality of SL-DRX Active Time durations including the SL-DRX Active Time duration corresponds to a static gap pattern over the history window.

3. The UE of claim 1 , wherein to determine the set of candidate slots of a number of slots that have been sensed, the processor is configured to:
detect at least q sensed periods including the sensed period of the plurality of sensed periods, wherein the set of candidate slots correspond to a selection window over the q sensed periods, wherein q is an integer less than or equal to p,
wherein p is an integer corresponding to a maximum number of sensed periods of the history window that are evaluated to detect the at least q sensed periods.

4. The UE of claim 1 , wherein to determine the set of candidate slots, the processor is configured to:
monitor a Physical Sidelink Control Channel (PSCCH) during the SL-DRX Active Time duration; and
determine candidate slots of the set of candidate slots associated with the PSCCH based at least on a projection of a selection window applied to measurements corresponding to the monitoring.

5. The UE of claim 3 , wherein the processor is further configured to: determine the selection window based on a packet delay budget of a packet corresponding to the first signal.

6. The UE of claim 1 , wherein the processor is further configured to:
wherein a SL-DRX cycle comprises the SL-DRX ON Duration and an SL-DRX SLEEP Duration, align a duration of the SL-DRX cycle with the sensed period of the plurality of sensed periods of the history window.

7. The UE of claim 1 , wherein to select the first candidate slot, the processor is configured to randomly select the first candidate slot of the subset of candidate slots.

8. The UE of claim 1 , wherein to determine the set of candidate slots that are sensed, the processor is further configured to:
determine a sum of actual SL-DRX SLEEP times over the history window;
determine an actual sleep ratio comprising: the sum of the actual SL-DRX SLEEP times divided by the history window;
determine that the actual sleep ratio satisfies a sleep ratio threshold;
based on the sleep ratio threshold being satisfied, randomly select a second candidate slot from a selection window; and
transmit via the transceiver, a second signal via the second candidate slot.

9. The UE of claim 1 , wherein to determine the set of candidate slots, the processor is configured to:
determine, for the first candidate slot of the subset of candidate slots, that a corresponding occupancy level over the history window satisfies the occupancy threshold.

10. The UE of claim 1 , wherein the processor is further configured to:
establish a sidelink (SL) configuration with a peer UE, wherein the peer UE performs full sensing;
discontinue determining the set of candidate slots that are sensed over the history window;
receive, via the transceiver, during the SL-DRX ON Duration, SL sensed measurements from the peer UE;
determine based at least on the SL sensed measurements, a positive candidate list;
select a second candidate slot from the positive candidate list; and
transmit via the transceiver, a second signal via the second candidate slot.

11. The UE of claim 10 , wherein the processor is further configured to:
transmit a radio resource control (RRC) signal to the peer UE soliciting the SL sensed measurements of the peer UE.

12. The UE of claim 10 , wherein the processor is further configured to:
establish a second SL connection with a pedestrian-UE (P-UE);
determine the second candidate slot based on the second SL connection that conflicts with the positive candidate list; and
exclude the second candidate slot from the positive candidate list.

13. The UE of claim 10 , wherein the processor is further configured to:
establish a second SL connection with a pedestrian-UE (P-UE), wherein the P-UE and the UE comprise a group; and
transmit the SL sensed measurements to the P-UE, wherein the P-UE does not perform sensing for candidate slots.

14. The UE of claim 10 , wherein the peer UE comprises: a vehicle UE (V-UE) or a road side unit (RSU).

15. A method for a user equipment (UE) system comprising:
determining a set of candidate slots of a number of slots that have been sensed over a plurality of sensed periods of a history window, wherein a sensed period of the plurality of sensed periods corresponds to a sidelink discontinuous reception (SL-DRX) Active Time duration that exceeds an SL-DRX ON Duration, and wherein the plurality of sensed periods is less than a plurality of periods of the history window;
determining a subset of candidate slots from the set of candidate slots based at least on an occupancy threshold;
selecting a first candidate slot from the subset of candidate slots; and
transmitting a first signal via the first candidate slot.

16. The method of claim 15 , wherein the determining the set of candidate slots of the number of slots that have been sensed comprises:
detecting at least q sensed periods including the sensed period of the plurality of sensed periods, wherein the set of candidate slots correspond to a selection window over the at least q sensed periods, wherein q is an integer greater than or equal to p,
wherein p is an integer corresponding to a maximum number of sensed periods of the history window that are evaluated to detect the at least q sensed periods.

17. The method of claim 15 , wherein the determining the set of candidate slots further comprises:
monitoring a Physical Sidelink Control Channel (PSCCH) during the SL-DRX Active Time duration; and
determining candidate slots of the set of candidate slots associated with the PSCCH based at least on a projection of a selection window applied to measurements corresponding to the monitoring.

18. The method of claim 15 , further comprising:
determining a sum of actual SL-DRX SLEEP times over the history window;
determining an actual sleep ratio comprising: the sum of the actual SL-DRX SLEEP times divided by the history window;
determining that the actual sleep ratio satisfies a sleep ratio threshold;
based on the sleep ratio threshold being satisfied, randomly selecting a second TX slot from a selection window; and
transmitting via a transceiver, a second signal via the second TX slot.

19. The method of claim 16 , further comprising:
establishing a sidelink (SL) configuration with a peer UE, wherein the peer UE performs full sensing;
discontinuing detecting the at least q sensed periods;
receiving via a transceiver, during the SL-DRX ON Duration, SL sensed measurements from the peer UE;
determining based at least on the SL sensed measurements, a positive candidate list;
selecting a second candidate slot from the positi

Assignees

• Apple Inc

Inventors

• Wu Zhibin
• Ye Chunxuan
• Sun Haitong
• Chen Yuqin
• Hu Haijing
• Zeng Wei
• Lovlekar Srirang A
• Gurumoorthy Sethuraman
• Venkata Naveen Kumar R Palle
• Kumar Adesh
• Zhang Dawei

Classifications

• H04W52/0225

  using monitoring of external events, e.g. the presence of a signal · CPC title

• H04W72/25

  between terminals via a wireless link, e.g. sidelink · CPC title

• H04W76/28 Primary

  Discontinuous transmission [DTX]; Discontinuous reception [DRX] · CPC title

• H04W92/18

  between terminal devices · CPC title

• H04W4/40

  for vehicles, e.g. vehicle-to-pedestrians [V2P] · CPC title