JOINT TRANSMISSION OF PRECODED AND UNPRECODED SOUNDING REFERENCE SIGNALS IN UPLINK

• US 20180097595A1
• Filed: 08/29/2017
• Published: 04/05/2018
• Est. Priority Date: 09/30/2016
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: HUANG, Yi, ZENG, Wei, CHEN, Wanshi, XU, Hao, JI, Tingfang
• Granted Patent: US 10,469,224 B2
• Time in Patent Office: Days
• CPC Class Codes: H04B 7/0404 the mobile station comprising multiple antennas, e.g. to provide uplink diversity
• CPC Class Codes: H04B 7/0413 MIMO systems
• CPC Class Codes: H04B 7/0615 of weighted versions of same signal
• CPC Class Codes: H04L 1/0009 by adapting the channel coding H04L1/1812 takes precedence
• CPC Class Codes: H04L 5/0037 Inter-user or inter-terminal allocation
• 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 88/02 Terminal devices
• CPC Class Codes: H04W 88/08 Access point devices

Abstract

Both precoded sounding reference signals (SRS) and unprecoded SRS are transmitted from a UE to an eNB. The UE may transmit both in the same subframe using either TDM or FDM. Or the UE may transmit each in different subframes from each other. The eNB uses some combination of the precoded SRS and the unprecoded SRS in scheduling resources for the UE. The eNB may also provide instruction to the UE for PUSCH precoding for data transmission. The eNB may signal the UE to use the same precoding as for the precoded SRS. The eNB may instead signal the UE to use different precoding by including the precoding information or delta information between the precoding used for the precoded SRS and the selected precoding for the PUSCH data.

Claims

1. A method, comprising:

generating, by a first wireless communications device, a precoded sounding reference signal (SRS);

generating, by the first wireless communications device, an unprecoded SRS separate from the precoded SRS; and

transmitting, by the first wireless communications device, the precoded SRS and the unprecoded SRS to a second wireless communications device via an uplink channel.

2. The method of claim 1, wherein:

the precoded SRS and the unprecoded SRS are configured for resource scheduling by the second wireless communications device, and

the generating the precoded sounding reference signal is based on a downlink reference signal received from the second wireless communications device.

3. The method of claim 1, wherein the transmitting further comprises:

transmitting the precoded SRS during a first symbol period of a subframe and transmitting the unprecoded SRS during a second symbol period of the subframe.

4. The method of claim 1, wherein the transmitting further comprises:

transmitting the precoded SRS during a symbol period of a subframe using a first plurality of frequency resources, and transmitting the unprecoded SRS during the symbol period of the subframe using a second plurality of frequency resources.

5. The method of claim 1, wherein the transmitting further comprises:

transmitting the precoded SRS during a first subframe and transmitting the unprecoded SRS during a second subframe after the first subframe.

6. The method of claim 1, further comprising:

receiving, by the first wireless communications device, a precode instruction from the second wireless communications device.

7. The method of claim 6, wherein the precode instruction directs the first wireless communications device to apply a precoding used for the precoded SRS for data transmission.

8. The method of claim 6, wherein the precode instruction identifies a precoding for data transmission to apply by the first wireless communications device.

9. The method of claim 6, wherein the precode instruction identifies a delta between a desired precoding and an existing precoding used for the precoded SRS, the method further comprising:

deriving, by the first wireless communications device, a data precoding for data transmission from a combination of the delta and the existing precoding; and

applying, by the first wireless communications device, the data precoding for data transmission.

10. A method, comprising:

receiving, by a first wireless communications device, a precoded sounding reference signal (SRS) from a second wireless communications device;

receiving, by the first wireless communications device, an unprecoded SRS separate from the precoded SRS from the second wireless communications device; and

determining, by the first wireless communications device, a resource scheduling for the second wireless communications device based on a combination of the precoded SRS and the unprecoded SRS.

11. The method of claim 10, wherein:

the receiving the precoded SRS comprises receiving during a first symbol period of a subframe, and

the receiving the unprecoded SRS comprises receiving during a second symbol period of the subframe.

12. The method of claim 10, wherein:

the receiving the precoded SRS comprises receiving during a symbol period of a subframe using a first plurality of resources, and

the receiving the unprecoded SRS comprises receiving during the symbol period of the subframe using a second plurality of frequency resources different from the first plurality of frequency resources.

13. The method of claim 10, wherein:

the receiving the precoded SRS comprises receiving the precoded SRS during a first subframe, and

the receiving the unprecoded SRS comprises receiving the unprecoded SRS during a second subframe after the first subframe.

14. The method of claim 10, further comprising:

generating, by the first wireless communications device, a precode instruction for the second wireless communications device for data transmission on an uplink channel.

15. The method of claim 14, wherein the precode instruction directs the second wireless communications device to apply a precoding used for the precoded SRS for data transmission.

16. The method of claim 14, wherein the generating further comprises:

determining, by the first wireless communications device, a delta between a desired precoding and an existing precoding used for the precoded SRS; and

including, by the first wireless communications device, the delta as the precode instruction.

17. An apparatus, comprising:

a processor configured to;

generate a precoded sounding reference signal (SRS); and

generate an unprecoded SRS separate from the precoded SRS; and

a transceiver configured to transmit the precoded SRS and the unprecoded SRS to a wireless communications device via an uplink channel.

18. The apparatus of claim 17, wherein:

the precoded SRS and the unprecoded SRS are configured for resource scheduling by the wireless communications device, and

the generating the precoded sounding reference signal is based on a downlink reference signal received from the wireless communications device.

19. The apparatus of claim 17, wherein the transceiver is further configured to:

transmit the precoded SRS during a first symbol period of a subframe and transmit the unprecoded SRS during a second symbol period of the subframe.

20. The apparatus of claim 17, wherein the transceiver is further configured to:

transmit the precoded SRS during a symbol period of a subframe using a first plurality of frequency resources, and transmit the unprecoded SRS during the symbol period of the subframe using a second plurality of frequency resources.

21. The apparatus of claim 17, wherein the transceiver is further configured to:

transmit the precoded SRS during a first subframe and transmit the unprecoded SRS during a second subframe after the first subframe.

22. The apparatus of claim 17, wherein the transceiver is further configured to:

receive a precode instruction from the wireless communications device.

23. The apparatus of claim 22, wherein the precode instruction directs the processor to apply a precoding used for the precoded SRS for data transmission.

24. The apparatus of claim 22, wherein the precode instruction identifies a precoding for data transmission to apply by the processor.

25. The apparatus of claim 22, wherein the precode instruction identifies a delta between a desired precoding and an existing precoding used for the precoded SRS, the processor further configured to:

derive a data precoding for data transmission from a combination of the delta and the existing precoding; and

apply the data precoding for data transmission.

26. An apparatus, comprising:

a transceiver configured to;

receive a precoded sounding reference signal (SRS) from a wireless communications device; and

receive an unprecoded SRS separate from the precoded SRS from the wireless communications device; and

a processor configured to determine a resource scheduling for the second wireless communications device based on a combination of the precoded SRS and the unprecoded SRS.

27. The apparatus of claim 26, wherein:

the transceiver is configured to receive the precoded SRS during a first symbol period of a subframe, and

the transceiver is configured to receive the unprecoded SRS during a second symbol period of the subframe.

28. The apparatus of claim 26, wherein:

the transceiver is configured to receive the precoded SRS during a symbol period of a subframe using a first plurality of resources, and

the transceiver is configured to receive the unprecoded SRS during the symbol period of the subframe using a second plurality of frequency resources different from the first plurality of frequency resources.

29. The apparatus of claim 26, wherein the processor is further configured to:

generate a precode instruction for the wireless communications device for data transmission on an uplink channel.

30. The apparatus of claim 29, wherein the processor is further configured to:

determine a delta between a desired precoding and an existing precoding used for the precoded SRS; and

include the delta as the precode instruction.