Systems and methods for beamforming in multi-input multi-output communication systems

• US 20060203794A1
• Filed: 07/20/2005
• Published: 09/14/2006
• Est. Priority Date: 03/10/2005
• Status: Abandoned Application

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Gore, Dhanajay Ashok, Gorokhov, Alexei, Sampath, Hemanth, Kadous, Tamer
• Application Number:
  US11/186,152
• Publication Number:
  US 20060203794A1
• Time in Patent Office: Days
• US Class Current: 370/344
• CPC Class Codes: H04B 7/0417 Feedback systems
• CPC Class Codes: H04B 7/0617 for beam forming
• 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 25/0224 using sounding signals
• CPC Class Codes: H04L 27/261 Details of reference signals
• CPC Class Codes: H04L 5/023 Multiplexing of multicarrier modulation signals multicarrier modulation H04L27/2601

Abstract

Methods and apparatuses are disclosed that utilize information from less than all transmission paths from a transmitter to form beamforming weights for transmission. In addition, methods and apparatuses are disclosed that utilize channel information, such as CQI, eigenbeam weights, and/or channel estimates, to form beamforming weights.

Claims

1. A wireless communication apparatus comprising:

at least two antennas; and

a processor configured to generate beamforming weights, for transmission of symbols to a wireless communication device, based upon channel information corresponding to a number of transmission paths, wherein the number of transmission paths is less than a total number of transmission paths from the wireless communication apparatus to the wireless communication device.

2. The wireless communication apparatus of claim 1, wherein the number of transmission paths is equal to the number of the at least two antennas.

3. The wireless communication apparatus of claim 1, wherein the channel information corresponds to one transmission path from each of the at least two antennas used for transmission.

4. The wireless communication apparatus of claim 1, wherein the channel information corresponds to one transmission path for each of the at least two antennas used for reception.

5. The wireless communication apparatus of claim 1, wherein the processor generates a channel matrix based upon the channel information and then generates beamforming weights utilizing the channel matrix.

6. The wireless communication apparatus of claim 5, wherein the processor decomposes the channel matrix by performing QR decomposition to generate the beamforming weights.

7. The wireless communication apparatus of claim 1, wherein the processor generates the channel information utilizing feedback received from the wireless communication device.

8. The wireless communication apparatus of claim 1, wherein the processor generates the channel information utilizing pilot symbols received from the wireless communication device.

9. The wireless communication apparatus of claim 1, wherein the processor generates the channel information utilizing feedback received from the wireless communication device and pilot symbols received from the wireless communication device.

10. The wireless communication apparatus of claim 1, wherein channel information comprises estimated channel information generated based upon a plurality of broadband pilot symbols.

11. The wireless communication apparatus of claim 1, wherein channel information comprises estimated channel information generated based upon a plurality of hop based pilot symbols.

12. The wireless communication apparatus of claim 1, wherein channel information comprises estimated channel information generated based upon a plurality of hop based pilot symbols and plurality of broadband pilot symbols.

13. The wireless communication apparatus of claim 1, wherein the processor further generates channel quality information, the channel quality information being based upon pilot symbols transmitted from at least one transmit antenna of a wireless communication device and received at the at least two antennas and wherein the channel information consists of the channel quality information.

14. The wireless communication apparatus of claim 13, wherein the channel quality information comprises signal to noise information.

15. The wireless communication apparatus of claim 1, wherein the processor is further configured to generate beamforming weights, for transmission of symbols to a wireless communication device, based upon both channel information and eigenbeam information.

30. The wireless communication apparatus of claim 15, wherein the means for generating comprises means for generating the beamforming weights based upon both channel information and eigenbeam information.

16. A wireless communication apparatus comprising:

at least two antennas; and

means for generating beamforming weights based upon channel information corresponding to a number of transmission paths less than a number of transmission paths from transmission antennas of the at least two antennas to a wireless communication device.

17. The wireless communication apparatus of claim 16, wherein the number of transmission paths is equal to the number of the at least two antennas.

18. The wireless communication apparatus of claim 16, wherein the channel information corresponds to one transmission path from each of the at least two antennas used for transmission.

19. The wireless communication apparatus of claim 16, wherein the channel information corresponds to one transmission path for each of the at least two antennas used for reception.

20. The wireless communication apparatus of claim 16, wherein channel information comprises estimated channel information generated based upon a plurality of broadband pilot symbols.

21. The wireless communication apparatus of claim 16, wherein channel information comprises estimated channel information generated based upon a plurality of hop based pilot symbols.

22. The wireless communication apparatus of claim 16, wherein channel information comprises estimated channel information generated based upon a plurality of hop based pilot symbols and plurality of broadband pilot symbols.

23. The wireless communication apparatus of claim 16, wherein the channel information comprises channel quality information.

24. The wireless communication apparatus of claim 23, wherein the channel quality information comprises signal to noise information.

25. The wireless communication apparatus of claim 16, further comprising means for generating a channel matrix based upon the channel information and wherein the means for generating the beamforming weights utilizes the channel matrix to generate the beamforming weights.

26. The wireless communication apparatus of claim 25, wherein the circuit decomposes the channel matrix comprises means for performing QR decomposition.

27. The wireless communication apparatus of claim 16, further comprising means for generating a channel matrix based upon feedback received from the wireless communication device and wherein the means for generating the beamforming weights utilizes the channel matrix to generate the beamforming weights.

28. The wireless communication apparatus of claim 16, further comprising means for generating a channel matrix based upon pilot symbols received from the wireless communication device and wherein the means for generating the beamforming weights utilizes the channel matrix to generate the beamforming weights.

29. The wireless communication apparatus of claim 16, further comprising means for generating a channel matrix based upon utilizing feedback received from the wireless communication device and pilot symbols received from the wireless communication device, and wherein the means for generating the beamforming weights utilizes the channel matrix to generate the beamforming weights.

31. A method for forming beamforming weights comprising:

reading channel information corresponding to a number of transmission paths, that is less than a number of transmission paths between a wireless transmitter and a wireless receiver;

generating beamforming weights based upon the channel information for transmission from the transmit antennas of the wireless transmitter.

32. The method of claim 31, wherein the number of transmission paths is less than a number of transmit antennas of the wireless transmitter.

33. The method of claim 31, wherein the channel information corresponds to one transmission path for each transmit antenna of the wireless transmitter.

34. The method of claim 31, wherein the channel information corresponds to one transmission path.

35. The method of claim 31, wherein channel information comprises estimated channel information generated based upon a plurality of broadband pilot symbols.

36. The method of claim 31, wherein channel information comprises estimated channel information generated based upon a plurality of hop based pilot symbols.

37. The method of claim 31, wherein channel information comprises estimated channel information generated based upon a plurality of hop based pilot symbols and plurality of broadband pilot symbols.

38. The method of claim 31, wherein the channel information comprises channel quality information.

39. The wireless communication apparatus of claim 38, wherein the channel quality information comprises signal to noise information.

42. The wireless communication apparatus of claim 38, wherein the processor generates a channel matrix based upon the channel information and then generates beamforming weights utilizing the channel matrix.

43. The wireless communication apparatus of claim 42, wherein the processor decomposes the channel matrix comprises means for performing QR decomposition.

44. The wireless communication apparatus of claim 42, wherein the processor generates the channel information utilizing feedback received from the wireless communication device.

45. The wireless communication apparatus of claim 42, wherein the processor generates the channel information utilizing pilot symbols received from the wireless communication device.

46. The wireless communication apparatus of claim 42, wherein the processor generates the channel information utilizing feedback received from the wireless communication device and pilot symbols received from the wireless communication device.

47. The wireless communication apparatus of claim 46, wherein the processor further generates channel quality information, the channel quality information being based upon pilot symbols transmitted from at least one transmit antenna of the wireless communication device and received at the at least two antennas and wherein the channel information consists of the channel quality information.

48. The wireless communication apparatus of claim 47, wherein the channel quality information comprises signal to noise information.

49. The wireless communication apparatus of claim 42, wherein the processor is further configured to generate beamforming weights, for transmission of symbols to a wireless communication device, based upon both channel information and eigenbeam information.

40. A wireless communication apparatus comprising:

at least two antennas; and

a processor configured to generate beamforming weights, for transmission of symbols to a wireless communication device, based upon channel information corresponding to a number of receive antennas of the wireless communication device, wherein the number of receive antennas is less than a total number of antennas utilized for reception at the wireless communication device.

41. The wireless communication apparatus of claim 40, wherein the number of receive antennas is equal to one.

50. A wireless communication apparatus comprising:

at least two antennas; and

means for generating beamforming weights based upon channel information corresponding to a number of channels less than a number of receive antennas at a wireless communication device.

51. The wireless communication apparatus of claim 50, wherein the number of receive antennas equal to one.

52. The wireless communication apparatus of claim 50, wherein the channel information comprises channel quality information.

53. The wireless communication apparatus of claim 52, wherein the channel quality information comprises signal to noise information.

54. The wireless communication apparatus of claim 50, further comprising means for generating a channel matrix based upon the channel information and wherein the means for generating the beamforming weights utilizes the channel matrix to generate the beamforming weights.

55. The wireless communication apparatus of claim 54, wherein the circuit decomposes the channel matrix comprises means for performing QR decomposition.

56. The wireless communication apparatus of claim 54, further comprising means for generating a channel matrix based upon feedback received from the wireless communication device and wherein the means for generating the beamforming weights utilizes the channel matrix to generate the beamforming weights.

57. The wireless communication apparatus of claim 54, further comprising means for generating a channel matrix based upon pilot symbols received from the wireless communication device and wherein the means for generating the beamforming weights utilizes the channel matrix to generate the beamforming weights.

58. The wireless communication apparatus of claim 54, further comprising means for generating a channel matrix based upon feedback received from the wireless communication device and pilot symbols received from the wireless communication device, and wherein the means for generating the beamforming weights utilizes the channel matrix to generate the beamforming weights.

59. The wireless communication apparatus of claim 50, wherein the means for generating comprises means for generating the beamforming weights based upon both channel information and eigenbeam information.