TECHNIQUES FOR BEAM SHAPING AT A MILLIMETER WAVE BASE STATION AND A WIRELESS DEVICE AND FAST ANTENNA SUBARRAY SELECTION AT A WIRELESS DEVICE

• US 20160198474A1
• Filed: 08/10/2015
• Published: 07/07/2016
• Est. Priority Date: 01/06/2015
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Raghavan, Vasanthan, Cezanne, Juergen, Subramanian, Sundar, Sampath, Ashwin, Li, Junyi
• Granted Patent: US 9,872,296 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: H04B 7/0456 Selection of precoding matrices or codebooks, e.g. using matrices antenna weighting
• CPC Class Codes: H04B 7/0617 for beam forming
• CPC Class Codes: H04B 7/0639 Using selective indices, e.g. of a codebook, e.g. pre-distortion matrix index [PMI] or for beam selection
• CPC Class Codes: H04B 7/0874 using subgroups of receive antennas
• CPC Class Codes: H04W 72/0466 the resource being a scrambling code
• CPC Class Codes: H04W 72/542 using measured or perceived quality

Abstract

Methods, systems, and devices are described for wireless communication at a user equipment (UE). A wireless communications system may improve UE discovery latency by dynamically selecting and switching beam forming codebooks at the millimeter wave base station and the wireless device. Selecting an optimal beam forming codebook may allow the wireless communication system to improve link margins between the base station without compromising resources. In some examples, a wireless device may determine whether the received signals from the millimeter wave base station satisfy established signal to noise (SNR) thresholds, and select an optimal beam codebook to establish communication. Additionally or alternately, the wireless device may further signal the selected beam codebook to the millimeter wave base station and direct the millimeter wave base station to adjust its codebook based on the selection.

Claims

1. A method of wireless communications, comprising:

receiving, at a wireless device, a first signal from a millimeter wave base station using a first beam codebook;

dynamically determining that a second beam codebook, different from the first beam codebook, is to be used on the first signal; and

transmitting a second signal to the millimeter wave base station requesting the millimeter wave base station to use the second beam codebook.

2. The method of claim 1, further comprising:

determining whether a quality of the first signal is above or below a first threshold;

wherein the dynamically determining that the second beam codebook is to be used is based at least in part on the determining whether the quality of the first signal is above or below the first threshold.

3. The method of claim 2, wherein the second signal comprises a signal energy estimate, a beamforming vector index, information for beamforming, or a combination thereof.

4. The method of claim 1, further comprising:

determining whether a quality of the first signal is above or below a second threshold; and

dynamically selecting the second beam codebook based at least in part on the determining whether the quality of the first signal is above or below the second threshold.

5. The method of claim 1, further comprising:

identifying a first receiver beam codebook used at the wireless device as being associated with the first beam codebook used by the millimeter wave base station; and

switching from the first receiver beam codebook to a second receiver beam codebook associated with the second beam codebook used by the millimeter wave base station.

6. The method of claim 2, further comprising:

adapting the first threshold based at least in part on a selection of the second beam codebook.

7. The method of claim 2, wherein the second beam codebook is selected in response to determining that the quality of signal falls below the first threshold.

8. The method of claim 1, wherein the second beam codebook is selected from a group comprising at least one of:

a coarse codebook;

an intermediate codebook;

a fine codebook;

a wireless-device specific codebook;

a beam negation codebook;

a codebook of beams trading off signal quality to a specific wireless device;

or

a combination of beamforming vectors from different codebooks.

9. The method of claim 1, wherein the second signal comprises a request for the millimeter wave base station to switch to the second beam codebook.

10. The method of claim 9, wherein the request for the millimeter wave base station to switch to the second beam codebook is based at least in part on at least one of:

hardware or software complexity issues for radio frequency chains, maintenance of link issues, or performance improvement with metrics such as rate, reliability, or a combination thereof.

11. The method of claim 9, further comprising:

transmitting the second signal via a random access channel (RACH) using a coarse codebook.

12. The method of claim 9, further comprising:

transmitting the second signal over a low-frequency carrier network coexisting with a millimeter wave carrier network.

13. The method of claim 9, wherein the second signal comprises a distress signal transmitted with a unique identification at a high code rate.

14. The method of claim 1, wherein the first signal is a directional primary synchronization signal (DPSS).

15. The method of claim 1, further comprising:

calculating a signal-to-noise ratio (SNR) of the first signal to determine a quality of the first signal.

16. An apparatus for wireless communications, comprising:

a processor;

memory in electronic communication with the processor; and

instructions stored in the memory;

wherein the instructions are executable by the processor to;

receive, at a wireless device, a first signal from a millimeter wave base station using a first beam codebook;

dynamically determine that a second beam codebook, different from the first beam codebook, is to be used on the first signal; and

transmit a second signal to the millimeter wave base station requesting the millimeter wave base station to use the second beam codebook.

17. The apparatus of claim 16, wherein the instructions are executable by the processor to:

determine whether a quality of the first signal is above or below a first threshold;

wherein the dynamically determining that the second beam codebook is to be used is based at least in part on the determining whether the quality of the first signal is above or below the first threshold.

18. The apparatus of claim 17, wherein the second signal comprises a signal energy estimate, a beamforming vector index, information for beamforming, or a combination thereof.

19. The apparatus of claim 16, wherein the instructions are executable by the processor to:

determine whether a quality of the first signal is above or below a second threshold; and

dynamically select the second beam codebook based at least in part on the determining.

20. The apparatus of claim 16, wherein the instructions are executable by the processor to:

identify a first receiver beam codebook used at the wireless device as being associated with the first beam codebook used by the millimeter wave base station; and

switch from the first receiver beam codebook to a second receiver beam codebook associated with the second beam codebook used by the millimeter wave base station.

21. The apparatus of claim 17, wherein the instructions are executable by the processor to:

adapt the first threshold based at least in part on a selection of the second beam codebook.

22. The apparatus of claim 17, wherein the second beam codebook is selected in response to determining that the quality of signal falls below the first threshold.

23. The apparatus of claim 16, wherein the second beam codebook is selected from a group comprising at least one of:

a coarse codebook;

an intermediate codebook;

a fine codebook;

a wireless-device specific codebook;

a beam negation codebook;

a codebook of beams trading off signal quality to a specific wireless device;

or

a combination of beamforming vectors from different codebooks.

24. The apparatus of claim 16, wherein the second signal comprises a request for the millimeter wave base station to switch to the second beam codebook.

25. An apparatus for wireless communications, comprising:

means for receiving, at a wireless device, a first signal from a millimeter wave base station using a first beam codebook;

means for dynamically determining that a second beam codebook, different from the first beam codebook, is to be used on the first signal; and

means for transmitting a second signal to the millimeter wave base station requesting the millimeter wave base station to use the second beam codebook.

26. The apparatus of claim 25, further comprising:

means for determining whether a quality of the first signal is above or below a first threshold;

wherein the dynamically determining that the second beam codebook is to be used is based at least in part on the determining whether the quality of the first signal is above or below the first threshold.

27. The apparatus of claim 26 wherein the second signal comprises a signal energy estimate, a beamforming vector index, information for beamforming, or a combination thereof.

28. The apparatus of claim 25, further comprising:

means for determining whether a quality of the first signal is above or below a second threshold; and

means for dynamically selecting the second beam codebook based at least in part on the determining.

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

receive, at the wireless device, a first signal from a millimeter wave base station using a first beam codebook;

dynamically determine that a second beam codebook, different from the first beam codebook, is to be used on the first signal; and

transmit a second signal to the millimeter wave base station requesting the millimeter wave base station to use the second beam codebook.

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

determine whether a quality of the first signal is above or below a first threshold;

wherein the dynamically determining that the second beam codebook is to be used is based at least in part on the determining whether the quality of the first signal is above or below the first threshold.

31. A method of communications at a wireless device, comprising:

receiving, at the wireless device, a first signal from a millimeter wave base station, the first signal beamformed on a plurality of beamforming vectors from a first codebook;

scanning at least a portion of a plurality of antenna subarrays to identify a quality of the first signal received at the portion of the plurality of antenna subarrays; and

selecting an antenna subarray from the scanned portion of the plurality of antenna subarrays based at least in part on the identified quality of the first signal.

32. The method of claim 31, wherein the scanning further comprises:

scanning at least the portion of the plurality of antenna subarrays with a plurality of beamforming vectors from a subarray selection codebook to identify the quality of the first signal received at the portion of the plurality of antenna subarrays.

33. The method of claim 32, further comprising:

selecting a first beamforming vector from the plurality of beamforming vectors from the subarray selection codebook for that subarray from the scanned portion of the plurality of antenna subarrays based at least on the identified quality of the first signal.

34. The method of claim 33, wherein the subarray selection codebook comprises at least one of:

a pseudo-omni beam pattern codebook;

an antenna selection codebook;

a coarse codebook;

an intermediate codebook;

a fine codebook;

a codebook designed to mitigate near-field impairments;

a codebook designed to assist in channel estimation;

or

a codebook designed to assist in radio-frequency design, reduce system complexity, or reduce system cost;

or

a combination of beamforming vectors from different codebooks.

35. The method of claim 31, further comprising:

initiating an on-demand search to identify a second beamforming vector from a plurality of beamforming vectors at the millimeter wave base station, wherein the second beamforming vector is identified from a group comprising at least one of a coarse codebook, an intermediate codebook, a fine codebook, a near-field impairment mitigation codebook, a channel estimation codebook, a complexity reduction codebook, or a wireless device specific codebook.

36. The method of claim 31, further comprising:

determining whether the quality of the first signal at the selected antenna subarray is above or below a first threshold; and

transmitting a second signal to the millimeter wave base station based at least in part on the determining.

37. The method of claim 36, further comprising:

receiving, at the wireless device, a third signal from the millimeter wave base station, the third signal beamformed on a plurality of beamforming vectors from a second codebook;

scanning a plurality of beamforming vectors from the second codebook; and

identifying a second beamforming vector from a plurality of beamforming vectors from the second codebook based at least in part on the scanning a plurality of beamforming vectors from the second codebook.

38. The method of claim 36, further comprising:

adapting the first threshold based at least in part on a selection of a beamforming vector by the wireless device.

39. The method of claim 36, further comprising:

transmitting the second signal via a random access channel (RACH).

40. The method of claim 36, further comprising:

transmitting the second signal over a low-frequency carrier network coexisting with a millimeter wave carrier network.

41. The method of claim 36, further comprising:

transmitting the second signal via a highly-coded low-rate channel/network already established with a unique identification.

42. The method of claim 36, wherein the second signal comprises a signal energy estimate, a beamforming vector index, information for beamforming, or a combination thereof.

43. The method of claim 36, further comprising:

calculating a signal-to-noise ratio of the first signal to determine the quality of the first signal.

44. The method of claim 31, wherein the first signal is a directional primary synchronization signal (DPSS).

45. An apparatus for wireless communications, comprising:

a processor;

memory in electronic communication with the processor; and

instructions stored in the memory;

wherein the instructions are executable by the processor to;

receive, at a wireless device, a first signal from a millimeter wave base station, the first signal beamformed on a plurality of beamforming vectors from a first codebook;

scan at least a portion of a plurality of antenna subarrays to identify a quality of the first signal received at the portion of the plurality of antenna subarrays; and

select an antenna subarray from the scanned portion of the plurality of antenna subarrays based at least in part on the identified quality of the first signal.

46. The apparatus of claim 45, wherein the instructions are executable by the processor to:

scan at least the portion of the plurality of antenna subarrays with a plurality of beamforming vectors from a subarray selection codebook to identify the quality of the first signal received at the portion of the plurality of antenna subarrays.

47. The apparatus of claim 46, wherein the instructions are executable by the processor to:

select a first beamforming vector from the plurality of beamforming vectors from the subarray selection codebook for that subarray from the scanned portion of the plurality of antenna subarrays based at least on the identified quality of the first signal.

48. The apparatus of claim 47, wherein the subarray selection codebook comprises at least one of:

a pseudo-omni beam pattern codebook;

an antenna selection codebook;

a coarse codebook;

an intermediate codebook;

a fine codebook;

a codebook designed to mitigate near-field impairments;

a codebook designed to assist in channel estimation;

a codebook designed to assist in radio-frequency design, reduce system complexity, or reduce system cost;

or a combination of beamforming vectors from different codebooks.

49. The apparatus of claim 45, wherein the instructions are executable by the processor to:

initiate an on-demand search to identify a second beamforming vector from a plurality of beamforming vectors at the millimeter wave base station, wherein the second beamforming vector is identified from a group comprising at least one of a coarse codebook, an intermediate codebook, a fine codebook, a near-field impairment mitigation codebook, a channel estimation codebook, a complexity reduction codebook, or a wireless device specific codebook.

50. The apparatus of claim 45, wherein the instructions are executable by the processor to:

determine whether the quality of the first signal at the selected antenna subarray is above or below a first threshold; and

transmit a second signal to the millimeter wave base station based at least in part on the determining.

51. The apparatus of claim 50, wherein the instructions are executable by the processor to:

receive, at the wireless device, a third signal from the millimeter wave base station, the third signal beamformed on a plurality of beamforming vectors from a second codebook;

scan a plurality of beamforming vectors from the second codebook; and

identify a second beamforming vector from a plurality of beamforming vectors from the second codebook based at least in part on the scanning a plurality of beamforming vectors from the second codebook.

52. The apparatus of claim 50, wherein the instructions are executable by the processor to:

adapt the first threshold based at least in part on a selection of a beamforming vector by the wireless device.

53. An apparatus for wireless communications, comprising:

means for receiving, at a wireless device, a first signal from a millimeter wave base station, the first signal beamformed on a plurality of beamforming vectors from a first codebook;

means for scanning at least a portion of a plurality of antenna subarrays to identify a quality of the first signal received at the portion of the plurality of antenna subarrays; and

means for selecting an antenna subarray from the scanned portion of the plurality of antenna subarrays based at least in part on the identified quality of the first signal.

54. The apparatus of claim 53, further comprising:

means for scanning at least the portion of the plurality of antenna subarrays with a plurality of beamforming vectors from a subarray selection codebook to identify the quality of the first signal received at the portion of the plurality of antenna subarrays.

55. The apparatus of claim 54, further comprising:

means for selecting a first beamforming vector from the plurality of beamforming vectors from the subarray selection codebook for that subarray from the scanned portion of the plurality of antenna subarrays based at least on the identified quality of the first signal.

56. The apparatus of claim 55, wherein the subarray selection codebook comprises at least one of:

a pseudo-omni beam pattern codebook;

an antenna selection codebook;

a coarse codebook;

an intermediate codebook;

a fine codebook;

a codebook designed to mitigate near-field impairments;

a codebook designed to assist in channel estimation;

a codebook designed to assist in radio-frequency design, reduce system complexity, or reduce system cost;

or

or a combination of beamforming vectors from different codebooks.

57. The apparatus of claim 53, further comprising:

means for initiating an on-demand search to identify a second beamforming vector from a plurality of beamforming vectors at the millimeter wave base station, wherein the second beamforming vector is identified from a group comprising at least one of a coarse codebook, an intermediate codebook, a fine codebook, a near-field impairment mitigation codebook, a channel estimation codebook, a complexity reduction codebook, or a wireless device specific codebook.

58. The apparatus of claim 53, further comprising

means for determining whether the quality of the first signal at the selected antenna subarray is above or below a first threshold;

and

means for transmitting a second signal to the millimeter wave base station based at least in part on the determining.

59. The apparatus of claim 58, further comprising:

means for receiving, at the wireless device, a third signal from the millimeter wave base station, the third signal beamformed on a plurality of beamforming vectors from a second codebook;

means for scanning a plurality of beamforming vectors from the second codebook;

means for identifying a second beamforming vector from a plurality of beamforming vectors from the second codebook based at least in part on the scanning a plurality of beamforming vectors from the second codebook.

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

receive, at the wireless device, a first signal from a millimeter wave base station, the first signal beamformed on a plurality of beamforming vectors from a first codebook;

scan at least a portion of a plurality of antenna subarrays to identify a quality of the first signal received at the portion of the plurality of antenna subarrays; and

select an antenna subarray from the scanned portion of the plurality of antenna subarrays based at least in part on the identified quality of the first signal.