Methods and apparatus to facilitate dual stage channel state information reference signal (CSI-RS) selection for CSI feedback

Patent metadata

Field	Value
Publication number	US-11496260-B2
Application number	US-201916449055-A
Country	US
Kind code	B2
Filing date	Jun 21, 2019
Priority date	Jun 21, 2019
Publication date	Nov 8, 2022
Grant date	Nov 8, 2022

Abstract

Apparatus, methods, and computer-readable media for facilitating dual stage CSI selection for CSI feedback are disclosed herein. An example method of wireless communication at a UE includes, after detecting a CSI report triggering event, selecting a subset of CSI-RS resources from a set of CSI-RS resources configured for the UE by applying at least one of an RSRP threshold or an SINR threshold to each CSI-RS resource of the set of CSI-RS resources. The example method also includes selecting a CSI-RS resource from the subset of CSI-RS resources based on an efficiency metric associated with each of the CSI-RS resources of the subset of CSI-RS resources. The example method also includes transmitting a CSI report to a base station, the CSI report including a CQI associated with the selected CSI-RS and at least one of a PMI, an RI, or a wideband component of the PMI.

First claim

What is claimed is:

1. A method of wireless communication at a user equipment (UE), comprising:
detecting a channel state information (CSI) report triggering event, wherein a set of CSI reference signal (CSI-RS) resources are configured from which a CSI-RS resource is to be selected for CSI reporting based on an efficiency metric;
measuring each CSI-RS resource of the set of CSI-RS resources based on at least one of a reference signal received power (RSRP) or a signal to interference and noise ratio (SINR);
applying a first threshold to each CSI-RS resource in the set of CSI-RS resources to select a first subset of CSI-RS resources that satisfy the first threshold and to discard CSI-RS resources remaining in the set of CSI-RS resources that do not satisfy the first threshold;
applying a second threshold to each CSI-RS resource remaining in the first subset of CSI-RS resources based on the first threshold to select a second subset of CSI-RS resources that satisfy the second threshold and to discard CSI-RS resources remaining in the first subset of CSI-RS resources that do not satisfy the second threshold;
calculating the efficiency metric for each CSI-RS resource remaining in the second subset of CSI-RS resources;
selecting the CSI-RS resource from the second subset of CSI-RS resources based on the efficiency metric associated with each CSI-RS resource in the second subset of CSI-RS resources; and
transmitting a CSI report to a base station, the CSI report including a channel quality indicator (CQI) associated with the selected CSI-RS resource and at least one of a precoding matrix indicator (PMI), a rank indication (RI), or a wideband component of the PMI.

2. The method of claim 1 , wherein the CSI report triggering event includes receiving at least one of a non-zero power CSI-RS for a channel measurement resource (CMR), a CSI interference measurement (CSI-IM) for an interference measurement resource (IMR), or a non-zero power CSI-RS for an interference measurement resource.

3. The method of claim 1 , wherein calculating the efficiency metric comprises obtaining a spectral efficiency measurement of each measured CSI-RS resource remaining in the second subset of CSI-RS resources, and wherein the selecting of the CSI-RS resource from the second subset of CSI-RS resources further includes mapping the spectral efficiency measurement to the CQI for the selected CSI-RS resource, wherein the efficiency metric of the selected CSI-RS resource indicates that the selected CSI-RS resource is associated with a highest spectral efficiency.

4. The method of claim 1 , wherein the second threshold corresponds to a RSRP threshold, wherein the selecting of the second subset of CSI-RS resources further includes:
comparing each measured RSRP to the RSRP threshold; and
selecting the respective CSI-RS resources with a measured RSRP that satisfy the RSRP threshold.

5. The method of claim 1 , wherein the second threshold corresponds to a SINR threshold, wherein the selecting of the second subset of CSI-RS resources further includes:
comparing each measured SINR to the SINR threshold; and
selecting respective CSI-RS resources with a measured SINR that satisfy the SINR threshold.

6. The method of claim 1 , wherein the first threshold corresponds to a RSRP threshold and the second threshold corresponds to a SINR threshold, wherein:
the first subset is determined by applying the RSRP threshold to each of the CSI-RS resources of the set of CSI-RS resources; and
the second subset is determined by applying the SINR threshold to each of the CSI-RS resources of the first subset.

7. The method of claim 1 , wherein the first threshold corresponds to a SINR threshold and the second threshold corresponds to a RSRP threshold, wherein:
the first subset is determined by applying the SINR threshold to each of the CSI-RS resources of the set of CSI-RS resources; and
the second subset is determined by applying the RSRP threshold to each of the CSI-RS resources of the first subset.

8. The method of claim 1 , wherein the first threshold or the second threshold corresponds to a RSRP threshold, wherein the RSRP threshold is a dynamic value that varies based on channel characteristics.

9. The method of claim 1 , wherein the first threshold or the second threshold corresponds to a RSRP threshold, wherein the RSRP threshold is a relative value based on a percentage of a total received power associated with the CSI-RS resources of the set of CSI-RS resources.

10. The method of claim 1 , wherein the first threshold or the second threshold corresponds to a SINR threshold, wherein the SINR threshold is a dynamic value that varies based on channel characteristics.

11. The method of claim 1 , wherein the first threshold or the second threshold corresponds to a SINR threshold, wherein the SINR threshold is a relative value based on a maximum SINR associated with the CSI-RS resources of the set of CSI-RS resources.

12. An apparatus of wireless communication, comprising:
means for detecting, at a user equipment (UE), a channel state information (CSI) report triggering event, wherein a set of CSI reference signal (CSI-RS) resources are configured from which a CSI-RS resource is to be selected for CSI reporting based on an efficiency metric;
means for measuring each CSI-RS resource of the set of CSI-RS resources based on at least one of a reference signal received power (RSRP) or a signal to interference and noise ratio (SINR);
means for applying a first threshold to each CSI-RS resource in the set of CSI-RS resources to select a first subset of CSI-RS resources that satisfy the first threshold and to discard CSI-RS resources remaining in the set of CSI-RS resources that do not satisfy the first threshold;
means for applying a second threshold to each CSI-RS resource remaining in the first subset of CSI-RS resources based on the first threshold to select a second subset of CSI-RS resources that satisfy the second threshold and to discard CSI-RS resources remaining in the first subset of CSI-RS resources that do not satisfy the second threshold;
means for calculating the efficiency metric for each CSI-RS resource remaining in the second subset of CSI-RS resources;
means for selecting the CSI-RS resource from the second subset of CSI-RS resources based on the efficiency metric associated with each CSI-RS resource in the second subset of CSI-RS resources; and
means for transmitting a CSI report to a base station, the CSI report including a channel quality indicator (CQI) associated with the selected CSI-RS resource and at least one of a precoding matrix indicator (PMI), a rank indication (RI), or a wideband component of the PMI.

13. The apparatus of claim 12 , wherein the means for detecting the CSI report triggering event further includes means for receiving at least one of a non-zero power CSI-RS for a channel measurement resource (CMR), a CSI interference measurement (CSI-IM) for an interference measurement resource (IMR), or a non-zero power CSI-RS for an interference measurement resource.

14. The apparatus of claim 12 , wherein the means for calculating the efficiency metric is further configured to obtain a spectral efficiency measurement of each measured CSI-RS resource remaining in the second subset of CSI-RS resources, and wherein the means for selecting the CSI-RS resource from the second subset of CSI-RS resources further includes means for mapping the spectral efficiency measurement to the CQI for the selected CSI-RS resource, wherein the efficiency metric of the selected CSI-RS resource indicates that the selected CSI-RS resource is associated with a highest spectral ef

Assignees

• Qualcomm Inc

Inventors

• Cheraghi Parisa
• Gorokhov Alexei Yurievitch

Classifications

• H04W72/54

  based on quality criteria · CPC title

• H04B7/0632

  Channel quality parameters, e.g. channel quality indicator [CQI] · CPC title

• H04W24/10

  Scheduling measurement reports {; Arrangements for measurement reports} · CPC title

• H04L5/0048 Primary

  Allocation of pilot signals, i.e. of signals known to the receiver (allocation of control signalling H04L5/0053; use of control signalling H04L5/0091) · CPC title

• H04B7/088 Primary

  using beam selection · CPC title