Channel measurement techniques in discontinuous reception scenarios

Patent metadata

Field	Value
Publication number	US-11503489-B2
Application number	US-202017024198-A
Country	US
Kind code	B2
Filing date	Sep 17, 2020
Priority date	Sep 18, 2019
Publication date	Nov 15, 2022
Grant date	Nov 15, 2022

Abstract

Methods, systems, and devices for wireless communications are described for configuring a user equipment (UE) for reference signal measurement while operating according to a discontinuous reception (DRX) configuration. The DRX configuration may include periodic DRX ON-durations, during which the UE is to be in an active mode for reception and transmission of signals, and between which the UE may transition to a low-power inactive mode. One or more reference signals may be scheduled for transmission by the base station during periods in which the UE may be in the inactive mode, and the UE may skip monitoring one or more of the reference signals while in the inactive mode. For one or more reference signal occasions, the UE may determine, based at least in part on a change in a channel quality metric, to be in a limited active mode in order to measure the reference signal.

First claim

What is claimed is:

1. A method for wireless communications at a user equipment (UE), comprising:
receiving a discontinuous reception cycle configuration that indicates a plurality of discontinuous reception cycles within a discontinuous reception period that each have an ON-duration during which the UE is to be in an active mode to monitor for transmissions from an access network entity, and wherein the UE transitions to an inactive mode after one or more of the ON-durations until a subsequent ON-duration, and at least a first channel measurement associated with a channel measurement schedule occurs when the UE is to be in the inactive mode of the discontinuous reception cycle configuration;
skipping at least one channel measurement prior to the first channel measurement based at least in part on the UE being in the inactive mode of the discontinuous reception cycle at a corresponding time of the at least one prior channel measurement; and
setting the UE to be in a limited active mode to perform the first channel measurement based at least in part on a change in a channel quality metric exceeding a threshold value for at least a predetermined period before the first channel measurement, the predetermined period including at least one skipped channel measurement.

2. The method of claim 1 , wherein:
the predetermined period corresponds to a predetermined quantity of skipped channel measurements.

3. The method of claim 2 , further comprising:
updating a counter of skipped channel measurements upon each occurrence of skipping a channel measurement; and
comparing a value of the counter to the predetermined quantity of skipped prior channel measurements to determine to maintain the UE in the limited active mode to perform the first channel measurement.

4. The method of claim 3 , wherein the counter of skipped channel measurements is updated when the UE transitions from the inactive mode to the active mode of the discontinuous reception cycle.

5. The method of claim 3 , further comprising:
performing the first channel measurement; and
resetting the counter of skipped channel measurements to an initial value responsive to the performing the first channel measurement.

6. The method of claim 1 , wherein the predetermined period is based on one or more of a preconfigured time duration, a magnitude of the change in the channel quality metric, or any combinations thereof.

7. The method of claim 6 , wherein a duration of the predetermined period is longer for a smaller magnitude of change in the channel quality metric, and is shorter for a larger magnitude of change in the channel quality metric.

8. The method of claim 1 , wherein the channel quality metric comprises one or more of a reference signal received power (RSRP), a reference signal received quality (RSRQ), or a signal to noise ratio (SNR), or any combinations thereof, that is determined based at least in part on one or more signals received from the access network entity.

9. The method of claim 1 , further comprising:
comparing a current value of the channel quality metric to a prior value of the channel quality metric prior to transitioning to the inactive mode.

10. The method of claim 9 , further comprising:
storing, after the comparing, the current value of the channel quality metric to replace the prior value of the channel quality metric.

11. The method of claim 1 , wherein the setting the UE to be in a limited active mode to perform the first channel measurement further comprises:
determining that at least a predetermined number of prior channel measurements have been skipped based on the UE being in the inactive mode during corresponding scheduled channel measurements of the channel measurement schedule, wherein the predetermined period corresponds to the predetermined number of prior channel measurements; and
determining that a difference between a current channel quality metric and a prior channel quality metric exceeds the threshold value.

12. The method of claim 1 , wherein the setting the UE to be in the limited active mode further comprises:
maintaining channel measurement components of the UE in an ON state and deactivating physical downlink control channel (PDCCH) decoding components following an ON-duration of a discontinuous reception cycle that is prior to the first channel measurement;
performing the first channel measurement; and
deactivating, responsive to performing the first channel measurement, the channel measurement components.

13. The method of claim 12 , wherein the channel measurement components are maintained in the ON state after expiration of the ON-duration based on the first channel measurement being within a predetermined time from the expiration of the ON-duration.

14. The method of claim 1 , wherein the setting the UE to be in the limited active mode further comprises:
transitioning channel measurement components and physical downlink control channel (PDCCH) decoding components of the UE to an inactive state following an ON-duration of a discontinuous reception cycle that is prior to the first channel measurement;
transitioning the channel measurement components to an ON state based at least in part on the channel measurement schedule associated with the first channel measurement;
performing the first channel measurement; and
deactivating, responsive to performing the first channel measurement, the channel measurement components.

15. The method of claim 14 , wherein the channel measurement components are transitioned to the ON state after expiration of the ON-duration based on the first channel measurement being between a predetermined time from the expiration of the ON-duration and from a start of a subsequent ON-duration.

16. The method of claim 1 , wherein the setting the UE to be in the limited active mode further comprises:
transitioning channel measurement components and physical downlink control channel (PDCCH) decoding components of the UE to an inactive state following an ON-duration of a discontinuous reception cycle that is prior to the first channel measurement;
transitioning the channel measurement components to an ON state based at least in part on the channel measurement schedule associated with the first channel measurement;
performing the first channel measurement; and
transitioning the PDCCH decoding components to the ON state for a subsequent ON-duration.

17. The method of claim 16 , wherein the channel measurement components are transitioned to the ON state prior to the subsequent ON-duration based on the first channel measurement being within a predetermined time from a start of the subsequent ON-duration.

18. An apparatus for wireless communications at a user equipment (UE), comprising:
a processor,
memory coupled with the processor; and
instructions stored in the memory and executable by the processor to cause the apparatus to:
receive a discontinuous reception cycle configuration that indicates a plurality of discontinuous reception cycles within a discontinuous reception period that each have an ON-duration during which the UE is to be in an active mode to monitor for transmissions from an access network entity, and wherein the UE transitions to an inactive mode after one or more of the ON-durations until a subsequent ON-duration, and at least a first channel measurement associated with a channel measurement schedule occurs when the UE is to be in the inactive mode of the discontinuous reception cycle configuration;
skip at least one channel measurement prior to the first channel measurement based at least in part

Assignees

• Qualcomm Inc

Inventors

• Rungta Pranay Sudeep
• Maheshwari Shailesh
• Kalyanappagol Sanjana Vijaykumar
• Verma Ankit

Classifications

• H04W72/23

  in the downlink direction of a wireless link, i.e. towards a terminal · CPC title

• H04L27/2601

  Multicarrier modulation systems · CPC title

• H04L25/0224

  using sounding signals · CPC title

• H04B17/336

  Signal-to-interference ratio [SIR] or carrier-to-interference ratio [CIR] · CPC title

• H04L5/0082

  at predetermined intervals · CPC title