MULTI-LAYER BEAMFORMING IN MILLIMETER-WAVE MULTIPLE-INPUT/MULTIPLE-OUTPUT SYSTEMS

• US 20170244451A1
• Filed: 06/21/2016
• Published: 08/24/2017
• Est. Priority Date: 02/22/2016
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Raghavan, Vasanthan, Subramanian, Sundar, Mukkavilli, Krishna Kiran, Sampath, Ashwin, Li, Junyi
• Granted Patent: US 11,196,462 B2
• Time in Patent Office: Days
• CPC Class Codes: H04B 17/336 Signal-to-interference ratio [SIR] or carrier-to-interference ratio [CIR]
• CPC Class Codes: H04B 7/0408 using two or more beams, i.e. beam diversity
• CPC Class Codes: H04B 7/0413 MIMO systems
• CPC Class Codes: H04B 7/0452 Multi-user MIMO systems
• CPC Class Codes: H04B 7/0617 for beam forming
• CPC Class Codes: H04B 7/0628 Diversity capabilities
• CPC Class Codes: H04B 7/063 Parameters other than those covered in groups H04B7/0623 - H04B7/0634, e.g. channel matrix rank or transmit mode selection
• CPC Class Codes: H04B 7/0632 Channel quality parameters, e.g. channel quality indicator [CQI]
• CPC Class Codes: H04L 7/04 Speed or phase control by synchronisation signals H04L7/0075 takes precedence
• CPC Class Codes: H04W 16/28 using beam steering
• CPC Class Codes: H04W 72/046 the resource being in the space domain, e.g. beams

Abstract

Methods, systems, and devices for wireless communication are described. A base station may identify two (or more) beamforming directions associated with simultaneous communications to a set of receivers. Each receiver may be associated with a different one of the two beamforming directions. The base station may schedule resources for simultaneous communications with the set of receivers based on the identified two beamforming directions. The base station may schedule simultaneous transmissions to the set of receivers using the scheduled resources.

Claims

1. A method for wireless communication comprising:

determining at least two beamforming directions associated with simultaneous communications to a set of receivers, wherein each receiver of the set of receivers is associated with a different one of the at least two beamforming directions;

identifying a performance metric associated with each receiver of the set of receivers, wherein the performance metric is based on a transmit power metric associated with a signal-to-noise ratio (SNR) associated with each receiver and a beamforming direction metric associated with an angle of departure associated with communications to each receiver;

determining the at least two beamforming directions based on the performance metric associated with each receiver;

scheduling resources for simultaneous communications with the set of receivers based on the identified at least two beamforming directions; and

scheduling simultaneous transmissions to the set of receivers using the scheduled resources.

2. The method of claim 1, wherein scheduling resources comprises:

scheduling the same time and frequency resource for the simultaneous communications with each receiver of the set of receivers.

3. The method of claim 1, wherein identifying the performance metric comprises:

transmitting a plurality of directional synchronization signals to a plurality of receivers from which the set of receivers is selected;

receiving, from each receiver of the plurality of receivers, a feedback message comprising communication parameters; and

identifying the performance metric for each receiver based on the communication parameters.

4. The method of claim 3, further comprising:

selecting the set of receivers from the plurality of receivers based on the performance metrics being within a predetermined range.

5. The method of claim 3, wherein the communication parameters comprise at least one of a beamforming direction index value associated with one or more directional synchronization signals, an SNR associated with each receiver, or combinations thereof.

6. The method of claim 3, wherein transmitting the plurality of directional synchronization signals comprises:

reusing a same resource element (RE) for transmitting the directional synchronization signals from a plurality of transmitter antenna ports, and

wherein the communication parameters comprise at least one of a receiver chain count value, a channel quality indicator (CQI), a data rate requirement, or combinations thereof.

7. The method of claim 1, wherein the performance metric is based on a difference in transmit power metric for each receiver being less than a first threshold value and based on a difference in beamforming direction metric being greater than a second threshold value.

8. The method of claim 1, further comprising:

transmitting a scheduling message to each receiver of the set of receivers, the scheduling message comprising an indication of the scheduled resources, wherein the scheduling message comprises a rank indicator (RI) associated with each receiver of the set of receivers.

9. An apparatus for wireless communication comprising:

means for determining at least two beamforming directions associated with simultaneous communications to a set of receivers, wherein each receiver of the set of receivers is associated with a different one of the at least two beamforming directions;

means for identifying a performance metric associated with each receiver of the set of receivers, wherein the performance metric is based on a transmit power metric associated with a signal-to-noise ratio (SNR) associated with each receiver and a beamforming direction metric associated with an angle of departure associated with communications to each receiver;

means for determining the at least two beamforming directions based on the performance metric associated with each receiver;

means for scheduling resources for simultaneous communications with the set of receivers based on the identified at least two beamforming directions; and

means for scheduling simultaneous transmissions to the set of receivers using the scheduled resources.

10. The apparatus of claim 9, further comprising:

means for scheduling the same time and frequency resource for the simultaneous communications with each receiver of the set of receivers.

11. The apparatus of claim 9, further comprising:

means for transmitting a plurality of directional synchronization signals to a plurality of receivers from which the set of receivers is selected;

means for receiving, from each receiver of the plurality of receivers, a feedback message comprising communication parameters; and

means for identifying the performance metric for each receiver based on the communication parameters.

12. The apparatus of claim 11, further comprising:

means for selecting the set of receivers from the plurality of receivers based on the performance metrics being within a predetermined range.

13. The apparatus of claim 11, wherein the communication parameters comprise at least one of a beamforming direction index value associated with one or more directional synchronization signals, an SNR associated with each receiver, or combinations thereof.

14. The apparatus of claim 11, further comprising:

means for reusing a same resource element (RE) for transmitting the directional synchronization signals from a plurality of transmitter antenna ports, and

wherein the communication parameters comprise at least one of a receiver chain count value, a channel quality indicator (CQI), a data rate requirement, or combinations thereof.

15. The apparatus of claim 9, wherein the performance metric is based on a difference in transmit power metric for each receiver being less than a first threshold value and based on a difference in beamforming direction metric being greater than a second threshold value.

16. The apparatus of claim 9, further comprising:

means for transmitting a scheduling message to each receiver of the set of receivers, the scheduling message comprising an indication of the scheduled resources, wherein the scheduling message comprises a rank indicator (RI) associated with each receiver of the set of receivers.

17. 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;

determine at least two beamforming directions associated with simultaneous communications to a set of receivers, wherein each receiver of the set of receivers is associated with a different one of the at least two beamforming directions;

identify a performance metric associated with each receiver of the set of receivers, wherein the performance metric is based on a transmit power metric associated with a signal-to-noise ratio (SNR) associated with each receiver and a beamforming direction metric associated with an angle of departure associated with communications to each receiver;

determine the at least two beamforming directions based on the performance metric associated with each receiver;

schedule resources for simultaneous communications with the set of receivers based on the identified at least two beamforming directions; and

schedule simultaneous transmissions to the set of receivers using the scheduled resources.

18. The apparatus of claim 17, wherein the instructions are operable to cause the processor to:

schedule the same time and frequency resource for the simultaneous communications with each receiver of the set of receivers.

19. The apparatus of claim 17, wherein the instructions are operable to cause the processor to:

transmit a plurality of directional synchronization signals to a plurality of receivers from which the set of receivers is selected;

receive, from each receiver of the plurality of receivers, a feedback message comprising communication parameters; and

identify the performance metric for each receiver based on the communication parameters.

20. The apparatus of claim 19, wherein the instructions are operable to cause the processor to:

select the set of receivers from the plurality of receivers based on the performance metrics being within a predetermined range.

21. The apparatus of claim 19, wherein the communication parameters comprise at least one of a beamforming direction index value associated with one or more directional synchronization signals, an SNR associated with each receiver, or combinations thereof.

22. The apparatus of claim 19, wherein the instructions are operable to cause the processor to:

reuse a same resource element (RE) for transmitting the directional synchronization signals from a plurality of transmitter antenna ports, and

wherein the communication parameters comprise at least one of a receiver chain count value, a channel quality indicator (CQI), a data rate requirement, or combinations thereof.

23. The apparatus of claim 17, wherein the performance metric is based on a difference in transmit power metric for each receiver being less than a first threshold value and based on a difference in beamforming direction metric being greater than a second threshold value.

24. A non-transitory computer-readable medium storing code for wireless communication, the code comprising instructions executable to:

determine at least two beamforming directions associated with simultaneous communications to a set of receivers, wherein each receiver of the set of receivers is associated with a different one of the at least two beamforming directions;

identify a performance metric associated with each receiver of the set of receivers, wherein the performance metric is based on a transmit power metric associated with a signal-to-noise ratio (SNR) associated with each receiver and a beamforming direction metric associated with an angle of departure associated with communications to each receiver;

determine the at least two beamforming directions based on the performance metric associated with each receiver;

schedule resources for simultaneous communications with the set of receivers based on the identified at least two beamforming directions; and

schedule simultaneous transmissions to the set of receivers using the scheduled resources.

25. The non-transitory computer-readable medium of claim 24, wherein the instructions are executable to:

schedule the same time and frequency resource for the simultaneous communications with each receiver of the set of receivers.

26. The non-transitory computer-readable medium of claim 24, wherein the instructions are executable to:

transmit a plurality of directional synchronization signals to a plurality of receivers from which the set of receivers is selected;

receive, from each receiver of the plurality of receivers, a feedback message comprising communication parameters; and

identify the performance metric for each receiver based on the communication parameters.

27. The non-transitory computer-readable medium of claim 26, wherein the instructions are executable to:

select the set of receivers from the plurality of receivers based on the performance metrics being within a predetermined range.

28. The non-transitory computer-readable medium of claim 26, wherein the communication parameters comprise at least one of a beamforming direction index value associated with one or more directional synchronization signals, an SNR associated with each receiver, or combinations thereof.

29. The non-transitory computer-readable medium of claim 26, wherein the instructions are executable to:

reuse a same resource element (RE) for transmitting the directional synchronization signals from a plurality of transmitter antenna ports, wherein the communication parameters comprise at least one of a receiver chain count value, a channel quality indicator (CQI), a data rate requirement, or combinations thereof.

30. The non-transitory computer-readable medium of claim 24, wherein the performance metric is based on a difference in transmit power metric for each receiver being less than a first threshold value and based on a difference in beamforming direction metric being greater than a second threshold value.