QUASI CO-LOCATION ASSUMPTIONS FOR APERIODIC CHANNEL STATE INFORMATION REFERENCE SIGNAL TRIGGERS

• US 20190229792A1
• Filed: 01/22/2019
• Published: 07/25/2019
• Est. Priority Date: 01/24/2018
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: JOHN WILSON, Makesh Pravin, LUO, Tao
• Granted Patent: US 11,239,893 B2
• Time in Patent Office: Days
• CPC Class Codes: H04B 7/024 Co-operative use of antennas of several sites, e.g. in co-ordinated multipoint or co-operative multiple-input multiple-output [MIMO] systems
• CPC Class Codes: H04B 7/0626 Channel coefficients, e.g. channel state information [CSI]
• CPC Class Codes: H04L 25/0226 sounding signals per se
• CPC Class Codes: H04L 5/0023 Time-frequency-space
• CPC Class Codes: H04L 5/0048 Allocation of pilot signals, i.e. of signals known to the receiver
• CPC Class Codes: H04L 5/0051 of dedicated pilots, i.e. pilots destined for a single user or terminal
• CPC Class Codes: H04W 72/0446 Resources in time domain, e.g. slots or frames
• CPC Class Codes: H04W 72/046 the resource being in the space domain, e.g. beams
• CPC Class Codes: H04W 72/23 in the downlink direction of a wireless link, i.e. towards a terminal

Abstract

Certain aspects of the present disclosure relate to quasi co-location assumptions for aperiodic channel state information (CSI) reference signals (RS) in communications systems operating according to NR techniques. An exemplary method that may be performed by a UE includes determining a quasi-co-location (QCL) relationship of an aperiodic channel state information (CSI) reference signal (CSI-RS) to a physical channel and processing the aperiodic CSI-RS according to the determined QCL relationship.

Claims

1. A method for wireless communications by a user equipment (UE), comprising:

determining a quasi-co-location (QCL) relationship of an aperiodic channel state information (CSI) reference signal (CSI-RS) to a physical channel; and

processing the aperiodic CSI-RS according to the determined QCL relationship.

2. The method of claim 1, wherein determining the QCL relationship is based on:

an offset parameter related to the aperiodic CSI-RS and a downlink control information (DCI) scheduling the aperiodic CSI-RS, and

a threshold value.

3. The method of claim 2, wherein determining the QCL relationship comprises determining to use a QCL relationship of a physical downlink control channel (PDCCH) of a control resource set (CORESET) having a lowest identifier (CORESET-ID), when the offset parameter is not yet determined by the UE.

4. The method of claim 2, wherein determining the QCL relationship comprises determining to use a QCL relationship of a physical downlink control channel (PDCCH) of a control resource set (CORESET) having a lowest identifier (CORESET-ID), when the offset parameter is lower than the threshold.

5. The method of claim 2, wherein determining the QCL relationship comprises determining to use a QCL relationship indicated in a grant of time and frequency resources of another transmission, wherein the granted time and frequency resources include time and frequency resources of the aperiodic CSI-RS, when the offset parameter is not yet determined by the UE.

6. The method of claim 2, wherein determining the QCL relationship comprises determining to use a QCL relationship indicated in a grant of time and frequency resources of another transmission, wherein the granted time and frequency resources include time and frequency resources of the aperiodic CSI-RS, when the offset parameter is lower than the threshold.

7. The method of claim 2, wherein determining the QCL relationship comprises determining to use a QCL relationship of a unicast physical downlink shared channel (PDSCH) on a set of time and frequency resources including time and frequency resources of the aperiodic CSI-RS, when the offset parameter is not yet determined by the UE.

8. The method of claim 2, wherein determining the QCL relationship comprises determining to use a QCL relationship of a unicast physical downlink shared channel (PDSCH) on a set of time and frequency resources including time and frequency resources of the aperiodic CSI-RS, when the offset parameter is lower than the threshold.

9. The method of claim 1, wherein determining the QCL relationship comprises:

determining the QCL relationship based on a QCL relationship for rate-matched resource elements (REs) indicated in a grant for a downlink data channel, wherein processing the aperiodic CSI-RS comprises processing the aperiodic CSI-RS in the rate-matched REs.

10. A method for wireless communications by a base station (BS), comprising:

determining a quasi-co-location (QCL) relationship of an aperiodic channel state information (CSI) reference signal (CSI-RS) to a physical channel; and

transmitting the aperiodic CSI-RS according to the determined QCL relationship.

11. The method of claim 10, wherein determining the QCL relationship is based on:

an offset parameter related to the aperiodic CSI-RS and a downlink control information (DCI) scheduling the aperiodic CSI-RS, and

a threshold value.

12. The method of claim 11, wherein determining the QCL relationship comprises determining to use a QCL relationship of a physical downlink control channel (PDCCH) of control resource set (CORESET) having a lowest identifier (CORESET ID), when the offset parameter is not yet determined.

13. The method of claim 11, wherein determining the QCL relationship comprises determining to use a QCL relationship of a physical downlink control channel (PDCCH) of control resource set (CORESET) having a lowest identifier (CORESET ID), when the offset parameter is lower than the threshold.

14. The method of claim 11, wherein determining the QCL relationship comprises determining to use a QCL relationship indicated in a grant of time and frequency resources of another transmission, wherein the granted time and frequency resources include time and frequency resources of the aperiodic CSI-RS, when the offset parameter is not yet determined.

15. The method of claim 11, wherein determining the QCL relationship comprises determining to use a QCL relationship indicated in a grant of time and frequency resources of another transmission, wherein the granted time and frequency resources include time and frequency resources of the aperiodic CSI-RS, when the offset parameter is lower than the threshold.

16. The method of claim 11, wherein determining the QCL relationship comprises determining to use a QCL relationship of a unicast physical downlink shared channel (PDSCH) on a set of time and frequency resources including time and frequency resources of the aperiodic CSI-RS, when the offset parameter is not yet determined.

17. The method of claim 11, wherein determining the QCL relationship comprises determining to use a QCL relationship of a unicast physical downlink shared channel (PDSCH) on a set of time and frequency resources including time and frequency resources of the aperiodic CSI-RS, when the offset parameter is lower than the threshold.

18. The method of claim 10, wherein determining the QCL relationship comprises

determining the QCL relationship based on a QCL relationship for resource elements (REs) rate-matched with the physical channel, and the method further comprises:

transmitting the physical channel according to another QCL relationship.

19. A method for wireless communications by a base station (BS), comprising:

determining a quasi-co-location (QCL) relationship of an aperiodic sounding reference signal (SRS) to a physical channel; and

processing the aperiodic SRS according to the determined QCL relationship.

20. The method of claim 19, wherein determining the QCL relationship is based on:

an offset parameter related to the aperiodic SRS and a downlink control information (DCI) scheduling the aperiodic SRS, and

a threshold value.

21. The method of claim 20, wherein determining the QCL relationship comprises determining to use a QCL relationship of a physical downlink control channel (PDCCH) of control resource set (CORESET) having a lowest identifier (CORESET-ID), when the offset parameter is not yet determined.

22. The method of claim 20, wherein determining the QCL relationship comprises determining to use a QCL relationship of a physical downlink control channel (PDCCH) of control resource set (CORESET) having a lowest identifier (CORESET-ID), when the offset parameter is lower than the threshold.

23. The method of claim 20, wherein determining the QCL relationship comprises determining to use a QCL relationship indicated in a grant of time and frequency resources of another transmission, wherein the granted time and frequency resources include time and frequency resources of the aperiodic SRS, when the offset parameter is not yet determined.

24. The method of claim 20, wherein determining the QCL relationship comprises determining to use a QCL relationship indicated in a grant of time and frequency resources of another transmission, wherein the granted time and frequency resources include time and frequency resources of the aperiodic SRS, when the offset parameter is lower than the threshold.

25. A method for wireless communications by a user equipment (UE), comprising:

determining a quasi-co-location (QCL) relationship of an aperiodic sounding reference signal (SRS) to a physical channel; and

transmitting the aperiodic SRS according to the determined QCL relationship.

26. The method of claim 25, wherein determining the QCL relationship is based on:

an offset parameter related to the aperiodic SRS and a downlink control information (DCI) scheduling the aperiodic SRS, and

a threshold value.

27. The method of claim 26, wherein determining the QCL relationship comprises determining to use a QCL relationship of a physical downlink control channel (PDCCH) of control resource set (CORESET) having a lowest identifier (CORESET-ID), when the offset parameter is not yet determined by the UE.

28. The method of claim 26, wherein determining the QCL relationship comprises determining to use a QCL relationship of a physical downlink control channel (PDCCH) of control resource set (CORESET) having a lowest identifier (CORESET-ID), when the offset parameter is lower than the threshold.

29. The method of claim 26, wherein determining the QCL relationship comprises determining to use a QCL relationship indicated in a grant of time and frequency resources of another transmission, wherein the granted time and frequency resources include time and frequency resources of the aperiodic SRS, when the offset parameter is not yet determined by the UE.

30. The method of claim 26, wherein determining the QCL relationship comprises determining to use a QCL relationship indicated in a grant of time and frequency resources of another transmission, wherein the granted time and frequency resources include time and frequency resources of the aperiodic SRS, when the offset parameter is lower than the threshold.