Channel state information reference signal (CSI-RS) for layer-3 (L3) mobility

Patent metadata

Field	Value
Publication number	US-10644777-B2
Application number	US-201715821210-A
Country	US
Kind code	B2
Filing date	Nov 22, 2017
Priority date	May 5, 2017
Publication date	May 5, 2020
Grant date	May 5, 2020

Abstract

A system and method for communicating channel state information reference signal (CSI-RS) in a communication network. A cell such as an eNodeB (eNB) or a transmit-receive-point (TRP) may transmit to a user equipment (UE) one or more synchronization signal (SS) blocks according to one or more beam directions available to the cell. Each beam direction may correspond to one or more antenna ports, and each SS block may correspond to an SS index. The cell may then transmit a CSI-RS signal configured according to the one or more antenna ports and the one or more SS blocks. In a different embodiment, the cell may select antenna ports of a neighbor cell for the CSI-RS signal based on a channel state measurement report of the neighbor cell received from the UE.

First claim

What is claimed is:

1. A method for communicating a channel state information reference signal (CSI-RS) in a communication network, the method comprising:
receiving, by a user equipment (UE) from a serving base station, one or more control signals indicating a CSI-RS configuration of a neighboring base station and a quasi-co-located (QCL) relationship between CSI-RS antenna ports of the neighboring base station and synchronization signal (SS) antenna ports of the neighboring base station;
receiving, by the UE, SS blocks from the neighboring base station over resources mapped to the SS antenna ports of the neighboring base station;
selecting, by the UE, a subset of the CSI-RS antenna ports of the neighboring base station based on a received signal quality of the SS blocks and the QCL relationship between the CSI-RS antenna ports of the neighboring base station and the SS antenna ports of the neighboring base station; and
receiving, by the UE, the CSI-RS from the neighboring base station over the subset of the CSI-RS antenna ports based on the CSI-RS configuration of the neighboring base station.

2. The method of claim 1 , wherein the subset of CSI-RS antenna ports of the neighboring base station comprises fewer than all CSI-RS antenna ports of the neighboring base station.

3. The method of claim 1 , wherein the receiving the one or more control signals indicating the CSI-RS configuration of the neighboring base station is prior to receiving the one or more SS blocks from the neighboring base station.

4. The method of claim 1 , further comprising:
sending, by the UE, a request for the CSI-RS configuration of the neighboring base station to the serving base station after receiving the one or more SS blocks from the neighboring base station, the indication of the CSI-RS configuration of the neighboring base station being received in response to the request for the CSI-RS configuration of the neighboring base station.

5. The method of claim 1 , wherein the one or more control signals indicating the CSI-RS configuration of the neighboring base station is received in a radio resource configuration (RRC) message.

6. The method of claim 1 , wherein each of the SS blocks is mapped to one or more CSI-RS antenna ports.

7. A user equipment (UE) comprising:
a processor; and
a non-transitory computer readable storage medium storing programming for execution by the processor, the programming including instructions to:
receive, from a serving base station, one or more control signals indicating a CSI-RS configuration of a neighboring base station and a quasi-co-located (QCL) relationship between CSI-RS antenna ports of the neighboring base station and synchronization signal (SS) antenna ports of the neighboring base station
receive SS blocks from the neighboring base station over resources mapped to the SS antenna ports of the neighboring base station;
select a subset of the CSI-RS antenna ports of the neighboring base station based on a received signal quality of the SS blocks and the QCL relationship between the CSI-RS antenna ports of the neighboring base station and the SS antenna ports of the neighboring base station; and
receive a CSI-RS from the neighboring base station over the subset of the CSI-RS antenna ports based on the CSI-RS configuration of the neighboring base station.

8. The UE of claim 7 , wherein the subset of CSI-RS antenna ports of the neighboring base station comprises fewer than all CSI-RS antenna ports of the neighboring base station.

9. The UE of claim 7 , wherein the UE receives the one or more control signals indicating the CSI-RS configuration of the neighboring base station prior to receiving the one or more SS blocks from the neighboring base station.

10. The UE of claim 7 , wherein the programming further include instructions to:
send a request for the CSI-RS configuration of the neighboring base station to the serving base station after receiving the one or more SS blocks from the neighboring base station, the indication of the CSI-RS configuration of the neighboring base station being received in response to the request for the CSI-RS configuration of the neighboring base station.

11. The UE of claim 7 , wherein the one or more control signals indicating the CSI-RS configuration of the neighboring base station is received in a radio resource configuration (RRC) message.

12. The UE of claim 7 , wherein each of the SS blocks is mapped to one or more CSI-RS antenna ports.

13. A non-transitory computer-readable medium storing computer instructions, that when executed by one or more processors of a user equipment (UE), cause the UE to perform the steps of:
receiving, from a serving base station, one or more control signals indicating a CSI-RS configuration of a neighboring base station and a quasi-co-located (QCL) relationship between CSI-RS antenna ports of the neighboring base station and synchronization signal (SS) antenna ports of the neighboring base station
receiving SS blocks from the neighboring base station over resources mapped to the SS antenna ports of the neighboring base station;
selecting a subset of the CSI-RS antenna ports of the neighboring base station based on a received signal quality of the SS blocks and the QCL relationship between the CSI-RS antenna ports of the neighboring base station and the SS antenna ports of the neighboring base station; and
receiving a CSI-RS from the neighboring base station over the subset of the CSI-RS antenna ports based on the CSI-RS configuration of the neighboring base station.

14. The non-transitory computer-readable medium of claim 13 , wherein the subset of CSI-RS antenna ports of the neighboring base station comprises fewer than all CSI-RS antenna ports of the neighboring base station.

15. The non-transitory computer-readable medium of claim 13 , wherein receiving the one or more control signals indicating the CSI-RS configuration of the neighboring base station is prior to receiving the one or more SS blocks from the neighboring base station.

16. The non-transitory computer-readable medium of claim 13 , wherein the one or more processors are caused to perform the step of sending a request for the CSI-RS configuration of the neighboring base station to the serving base station after receiving the one or more SS blocks from the neighboring base station, the indication of the CSI-RS configuration of the neighboring base station being received in response to the request for the CSI-RS configuration of the neighboring base station.

17. The non-transitory computer-readable medium of claim 13 , wherein the one or more control signals indicating the CSI-RS configuration of the neighboring base station is received in a radio resource configuration (RRC) message.

18. The non-transitory computer-readable medium of claim 13 , wherein each of the SS blocks is mapped to one or more CSI-RS antenna ports.

Assignees

• Huawei Tech Co Ltd

Inventors

• Baligh Mohammadhadi
• Au Kelvin Kar Kin
• Zarifi Keyvan

Classifications

• H04L5/006

  Quality of the received signal, e.g. BER, SNR, water filling · CPC title

• H04L5/0094

  Indication of how sub-channels of the path are allocated · CPC title

• H04B7/043

  using best eigenmode, e.g. beam forming or beam steering · CPC title

• H04W48/12

  using downlink control channel · CPC title

• H04W56/003

  Arrangements to increase tolerance to errors in transmission or reception timing · CPC title