CHANNEL STATE INFORMATION ESTIMATION AND CHANNEL INFORMATION REPORTING

• US 20170302352A1
• Filed: 12/05/2016
• Published: 10/19/2017
• Est. Priority Date: 04/18/2016
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Islam, Muhammad Nazmul, Mukkavilli, Krishna Kiran, Cezanne, Juergen, Luo, Tao, Subramanian, Sundar, Li, Junyi
• Granted Patent: US 10,097,254 B2
• Time in Patent Office: Days
• CPC Class Codes: H04B 7/0626 Channel coefficients, e.g. channel state information [CSI]
• CPC Class Codes: H04L 25/0204 of multiple channels
• CPC Class Codes: H04L 25/0228 with direct estimation from sounding signals
• 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 5/0057 Physical resource allocation for CQI
• CPC Class Codes: H04W 72/21 in the uplink direction of a wireless link, i.e. towards the network
• CPC Class Codes: H04W 72/23 in the downlink direction of a wireless link, i.e. towards a terminal
• CPC Class Codes: H04W 72/541 using the level of interference

Abstract

Methods, systems, and devices for wireless communication are described. A base station may transmit a phase noise correction reference signal (PC-RS) and a channel state information reference signal (CSI-RS) during a symbol period of a subframe. A user equipment (UE) may identify a first channel information using the PC-RS and the CSI-RS. The UE may transmit a channel information message to the base station that includes the first channel information. The first channel information may include a phase noise corrected channel measurement. The UE may the CSI-RS during the symbol period. Channel and phase noise estimates may be generated using a joint estimation based on the CSI-RS. The CSI-RS may be repeated periodically. In some cases, the UE may additionally or alternatively receive pilot tones that may include PC-RSs. The joint estimation may be further based on the pilot tones.

Claims

1. A method of wireless communication comprising:

receiving, at a user equipment (UE) during a symbol period, at least one phase noise compensation reference signal (PC-RS) and at least one channel state information reference signal (CSI-RS);

identifying a first channel information based at least in part on both the CSI-RS and the PC-RS; and

transmitting a channel information message to a base station, the channel information message comprising the first channel information.

2. The method of claim 1, further comprising:

identifying a second channel information based at least in part on the CSI-RS.

3. The method of claim 2, further comprising:

generating the channel information message that comprises the first channel information and the second channel information; and

transmitting the channel information message to the base station, the channel information message further comprising the second channel information.

4. The method of claim 2, further comprising:

identifying a channel measurement based at least in part on the CSI-RS, the second channel information comprising a non-phase noise corrected channel measurement.

5. The method of claim 2, wherein the first channel information and the second channel information comprises at least one of a channel quality information (CQI), a rank indicator, a precoding matrix indicator, a beam indicator, or combinations thereof

6. The method of claim 1, further comprising:

identifying a channel measurement based at least in part on the CSI-RS; and

identifying a phase noise correction factor based at least in part on the PC-RS, the first channel information comprising a phase noise corrected channel measurement

7. The method of claim 1, further comprising:

receiving, from the base station, a channel reporting format message that comprises a format indicator for the channel information message.

8. The method of claim 7, wherein the channel reporting format message is received on a physical downlink control channel (PDCCH).

9. The method of claim 8, further comprising:

decoding a one or more bits in a downlink control indicator (DCI) that conveys an indication of the format indicator for the channel information message.

10. The method of claim 7, wherein the format indicator comprises at least one of a request for the UE to report the first channel information or a second channel information or a request for the UE to report both the first channel information and the second channel information.

11. The method of claim 1, wherein the channel information message is transmitted on a physical uplink control channel (PUCCH).

12. The method of claim 1, wherein the channel information message is transmitted in a random access channel (RACH) subframe.

13. The method of claim 1, wherein the channel information message is transmitted in an uplink control information (UCI) of a physical uplink shared channel (PUSCH).

14. The method of claim 1, further comprising:

generating a channel estimate and a phase noise estimate using a joint estimation based at least in part on the CSI-RS; and

transmitting the channel information message to the base station based at least in part on the channel estimate and the phase noise estimate.

15. The method of claim 14, further comprising:

identifying a plurality of pilot tones adjacent to each other, wherein the joint estimation is based at least in part on the plurality of pilot tones and the plurality of pilot tones are surrounded in a frequency domain by a plurality of null tones.

16. The method of claim 15, further comprising:

adjusting a location of the plurality of pilot tones in the frequency domain, wherein the adjusting is based at least in part on a frequency hopping pattern.

17. The method of claim 15, further comprising:

determining a category associated with a receiving device; and

adjusting a number of the plurality of pilot tones based at least in part on the determined category.

18. The method of claim 14, further comprising:

receiving a periodic signal comprising at least one repetition of the CSI-RS, wherein the joint estimation is based at least in part on the periodic signal, wherein the periodic signal in time domain is generated by inserting a CSI-RS tone in every n-th tone of the periodic signal and by inserting null values in other tones of the periodic signal.

19. The method of claim 18, further comprising:

identifying a time periodicity of the periodic signal; and

determining a phase noise variation based at least in part on the CSI-RS, the periodic signal, and the time periodicity of the periodic signal, wherein the joint estimation is based at least in part on the phase noise variation.

20. A method of wireless communication comprising:

transmitting, to a user equipment (UE) during a symbol period, at least one phase noise compensation reference signal (PC-RS) and at least one channel state information reference signal (CSI-RS); and

receiving a channel information message comprising a first channel information, the first channel information is based at least in part on the CSI-RS and the PC-RS.

21. The method of claim 20, wherein the first channel information comprises a phase noise corrected channel measurement.

22. The method of claim 20, further comprising:

transmitting, to the UE, a channel reporting format message that comprises a format indicator for the channel information message, wherein the channel reporting format message is transmitted on a physical downlink control channel (PDCCH).

23. The method of claim 22, wherein the format indicator comprises at least one of a request for the UE to report the first channel information or a second channel information or a request for the UE to report the first channel information and the second channel information.

24. The method of claim 22, further comprising:

reserving one or more bits in a downlink control indicator (DCI) to convey an indication of the format indicator for the channel information message.

25. The method of claim 20, further comprising:

receiving the channel information message from the UE, the channel information message based at least in part on a channel estimate and a phase noise estimate generated using a joint estimation based at least in part on the CSI-RS.

26. The method of claim 25, further comprising:

transmitting a periodic signal comprising at least one repetition of the CSI-RS, wherein the joint estimation is based at least in part on the periodic signal.

27. An apparatus for wireless communication, comprising:

a processor;

memory in electronic communication with the processor; and

instructions stored in the memory and operable, when executed by the processor, to cause the apparatus to;

receive, at a user equipment (UE) during a symbol period, at least one phase noise compensation reference signal (PC-RS) and at least one channel state information reference signal (CSI-RS);

identify a first channel information based at least in part on both the CSI-RS and the PC-RS; and

transmit a channel information message to a base station, the channel information message comprising the first channel information.

28. The apparatus of claim 27, wherein the instructions are operable to cause the processor to cause the apparatus to:

generate a channel estimate and a phase noise estimate using a joint estimation based at least in part on the CSI-RS; and

transmit the channel information message to the base station based at least in part on the channel estimate and the phase noise estimate.

29. An apparatus for wireless communication, comprising:

a processor;

memory in electronic communication with the processor; and

instructions stored in the memory and operable, when executed by the processor, to cause the apparatus to;

transmit, to a user equipment (UE) during a symbol period, at least one phase noise compensation reference signal (PC-RS) and at least one channel state information reference signal (CSI-RS); and

receive a channel information message comprising a first channel information, the first channel information is based at least in part on the CSI-RS and the PC-RS.

30. The apparatus of claim 29, wherein the instructions are operable to cause the processor to cause the apparatus to:

receive the channel information message from the UE, the channel information message based at least in part on a channel estimate and a phase noise estimate generated using a joint estimation based at least in part on the CSI-RS.