System and method for communications system training

Patent metadata

Field	Value
Publication number	US-11277175-B2
Application number	US-202016857867-A
Country	US
Kind code	B2
Filing date	Apr 24, 2020
Priority date	May 18, 2018
Publication date	Mar 15, 2022
Grant date	Mar 15, 2022

Abstract

A method for operating a communication device includes receiving a first transmission including a first signal on one or more resources associated with signal reception, deriving a receive filter in accordance with the received first transmission, deriving a transmit filter in accordance with the receive filter, precoding a second signal with the transmit filter, thereby producing a second transmission, and transmitting the second transmission.

First claim

What is claimed is:

1. A method for operating a user equipment (UE), the method comprising:
receiving, by the UE, a downlink reference signal from one or more access nodes and processing the downlink reference signal in accordance with a spatial receive filter;
precoding, by the UE, an uplink reference signal in accordance with a spatial transmission filter to produce a precoded uplink reference signal, the spatial transmission filter derived from the spatial receive filter, with antenna ports of the downlink reference signal being mapped to antenna ports of the precoded uplink reference signal based on a one-to-one mapping relationship; and
transmitting, by the UE, the precoded uplink reference signal to the one or more access nodes.

2. The method of claim 1 , wherein a number of the antenna ports of the precoded uplink reference signal equals a number of the antenna ports of the downlink reference signal.

3. The method of claim 2 , wherein the spatial transmission filter is derived from the spatial receive filter according to weights associated with the antenna ports of the downlink reference signal, different weights being associated with different antenna ports of the downlink reference signal.

4. The method of claim 1 , wherein the spatial transmission filter is a conjugate transposed version of the spatial receive filter.

5. The method of claim 1 , wherein the spatial transmission filter is a conjugated version of the spatial receive filter.

6. The method of claim 1 , wherein the spatial transmission filter is a scaled version of the spatial receive filter.

7. The method of claim 1 , wherein the spatial transmission filter is a normalized version of the spatial receive filter.

8. The method of claim 1 , wherein the spatial transmission filter is identical to the spatial receive filter.

9. The method of claim 1 , wherein the downlink reference signal and the precoded uplink reference signal are received and transmitted over the same frequency subbands.

10. The method of claim 9 , wherein each portion of the spatial transmission filter is derived from a portion of the spatial receive filter corresponding to the same frequency subband as the derived portion of the spatial transmission filter.

11. The method of claim 1 , wherein the spatial transmission filter comprises a multi-antenna precoder, dimensions of the multi-antenna precoder being based on a number of the antenna ports of the precoded uplink reference signal and a number of transmit antenna ports of the UE, dimensions of a multi-antenna combiner of the spatial receive filter being based on a number of receive antenna ports of the UE and a number of the antenna ports of the downlink reference signal.

12. The method of claim 1 , wherein the downlink reference signal is a non-zero-power (NZP) channel state information RS (CSI-RS).

13. The method of claim 12 , wherein the NZP CSI-RS is received over NZP CSI-RS resource(s) for channel measurement specified via at least one of a radio resource control (RRC) message, a media access control (MAC) message, or a downlink control indication (DCI) message.

14. The method of claim 12 , wherein the NZP CSI-RS is received over NZP CSI-RS resource(s) for interference measurement specified via at least one of a radio resource control (RRC) message, a media access control (MAC) message, or a downlink control indication (DCI) message.

15. The method of claim 12 , wherein the NZP CSI-RS is received together with channel state information (CSI) interference measurement resource(s) specified via at least one of a radio resource control (RRC) message, a media access control (MAC) message, or a downlink control indication (DCI) message.

16. The method of claim 1 , wherein the downlink reference signal is a demodulation reference signal (DMRS).

17. The method of claim 16 , wherein the DMRS is configured to support a downlink data transmission over a physical downlink shared channel (PDSCH).

18. The method of claim 17 , wherein the downlink data transmission over the PDSCH has the same transmission rank as a number of the antenna ports of the downlink reference signal or a number of spatial layers of the DMRS.

19. The method of claim 18 , wherein a transmission rank of the downlink data transmission over the PDSCH identifies a number of transmission layers in the downlink data transmission over the PDSCH.

20. The method of claim 1 , wherein the precoded uplink reference signal is a sounding reference signal (SRS).

21. The method of claim 1 , wherein the precoded uplink reference signal is a demodulation reference signal (DMRS).

22. The method of claim 21 , wherein the DMRS is configured to support an uplink data transmission over a physical uplink shared channel (PUSCH).

23. The method of claim 22 , wherein the uplink data transmission over the PUSCH has the same transmission rank as a number of the antenna ports of the downlink reference signal or a number of spatial layers of the DMRS.

24. The method of claim 23 , wherein a transmission rank of the uplink data transmission over the PUSCH identifies a number of transmission layers in the uplink data transmission over the PUSCH.

25. A user equipment (UE) comprising:
a least one processor; and
a non-transitory computer readable storage medium in communication with the at least one processor, the computer readable storage media storing programming for execution by the at least one processor, the programming including instructions to:
receive a downlink reference signal from one or more access nodes and process the downlink reference signal in accordance with a spatial receive filter;
precode an uplink reference signal in accordance with a spatial transmission filter to produce a precoded uplink reference signal, the spatial transmission filter derived from the spatial receive filter, with antenna ports of the downlink reference signal being mapped to antenna ports of the precoded uplink reference signal based on a one-to-one mapping relationship; and
transmit the precoded uplink reference signal to the one or more access nodes.

Assignees

• Futurewei Technologies Inc

Inventors

• Maamari Diana
• Liu Jialing
• Cheng Qian
• Xiao Weimin
• Zhou Hao
• Soong Anthony C K

Classifications

• H04W72/541

  using the level of interference · CPC title

• H04W72/23

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

• H04B7/0417 Primary

  Feedback systems · CPC title

• H04L5/001

  the frequencies being arranged in component carriers · CPC title

• H04B7/0626

  Channel coefficients, e.g. channel state information [CSI] · CPC title