Method and System for Rate Selection Algorithm to Maximize Throughput in Close Loop Multiple Input Multiple Output (MIMO) Wireless Local Area Network (WLAN) System

• US 20090161641A1
• Filed: 12/18/2008
• Published: 06/25/2009
• Est. Priority Date: 01/17/2005
• Status: Active Grant

• Current Assignee: Avago Technologies International Sales Pte Limited (Broadcom, Inc.)
• Original Assignee: Broadcom Corporation (Broadcom, Inc.)
• Inventors: Kim, Joonsuk
• Granted Patent: US 8,270,432 B2
• Time in Patent Office: Days
• US Class Current: 370/338
• CPC Class Codes: H04B 7/0417 Feedback systems
• CPC Class Codes: H04L 1/0003 by switching between different modulation schemes
• CPC Class Codes: H04L 1/0009 by adapting the channel coding H04L1/1812 takes precedence
• CPC Class Codes: H04L 1/0025 Transmission of mode-switching indication
• CPC Class Codes: H04L 1/0068 by puncturing
• CPC Class Codes: H04L 1/0071 Use of interleaving interleaving per se H03M13/27
• CPC Class Codes: H04L 1/0618 Space-time coding
• CPC Class Codes: H04L 47/25 with rate being modified by the source upon detecting a change of network conditions
• CPC Class Codes: H04L 67/61 taking into account QoS or priority requirements
• CPC Class Codes: H04L 69/14 Multichannel or multilink protocols
• CPC Class Codes: H04W 28/18 Negotiating wireless communication parameters
• CPC Class Codes: H04W 28/22 Negotiating communication rate
• CPC Class Codes: H04W 84/12 WLAN [Wireless Local Area Networks]
• CPC Class Codes: Y02D 30/50 in wire-line communication networks, e.g. low power modes or reduced link rate

Abstract

Aspects of a method and system for rate selection algorithm to maximize throughput in closed loop multiple input multiple output (MIMO) wireless local area network (WLAN) system are provided and may comprise computing a maximum number of binary bits to be, simultaneously transmitted via an RF channel based on signal quality. A modulation technique may be selected based on the computed maximum, communicating feedback information comprising the selected modulation technique. Subsequently transmitted data may be received via an RF channel which is modulated based on the feedback information. Another aspect of the method may comprise receiving feedback information comprising at least one of a selected modulation technique and coding rate via an RF channel, and transmitting subsequent data via said at least one of a plurality of RF channels which either modulated, or coded, based on the feedback information.

Claims

1-22. -22. (canceled)

23. A method for communicating information in a communication system, the method comprising:

determining a rank value of a full channel estimate matrix based on signals received via one or more downlink RF channels; and

communicating, via one or more uplink RF channels, feedback information comprising said rank value.

24. The method according to claim 23, comprising determining said rank value of said full channel estimate matrix based on a computed matrix of singular values.

25. The method according to claim 24, wherein said rank value is equal to the number of nonzero singular values in said computed matrix of singular values.

26. The method according to claim 24, comprising communicating said computed matrix of singular values via said feedback information.

27. The method according to claim 24, comprising communicating, via said feedback information, one or both of a number of rows in said computed matrix of singular values and a number of columns in said computed matrix of singular values.

28. The method according to claim 23, comprising computing said full channel estimate matrix based on preamble information received via said received signals.

29. The method according to claim 28, comprising computing a computed matrix of singular values based on a singular value decomposition of said computed full channel estimate matrix.

30. The method according to claim 23, comprising determining one or more signal quality values based on said received signals.

31. The method according to claim 30, comprising determining said one or more signal quality values based on at least a portion of computed singular values.

32. The method according to claim 31, comprising communicating, via said one or more uplink RF channels, said determined one or more signal quality values.

33. The method according to claim 32, wherein said one or more signal quality values are signal to noise ratios.

34. The method according to claim 23, wherein said rank value is greater than or equal to 1 and less than or equal to a minimum value selected from a number of transmitting antennas and a number of receiving antennas.

35. A system for communicating information in a communication system, the system comprising:

one or more circuits that are operable to determine a rank value of a full channel estimate matrix based on signals received via one or more downlink RF channels; and

said one or more circuits are operable to communicate, via one or more uplink RF channels, feedback information comprising said rank value.

36. The system according to claim 35, wherein said one or more circuits are operable to determine said rank value of said full channel estimate matrix based on a computed matrix of singular values.

37. The system according to claim 36, wherein said rank value is equal to the number of nonzero singular values in said computed matrix of singular values.

38. The system according to claim 36, wherein said one or more circuits are operable to communicate said computed matrix of singular values via said feedback information.

39. The system according to claim 36, wherein said one or more circuits are operable to communicate, via said feedback information, one or both of a number of rows in said computed matrix of singular values and a number of columns in said computed matrix of singular values.

40. The system according to claim 35, wherein said one or more circuits are operable to compute said full channel estimate matrix based on preamble information received via said received signals.

41. The system according to claim 40, wherein said one or more circuits are operable to compute a computed matrix of singular values based on a singular value decomposition of said computed full channel estimate matrix.

42. The system according to claim 35, wherein said one or more circuits are operable to determine one or more signal quality values based on said received signals.

43. The system according to claim 42, wherein said one or more circuits are operable to determine said one or more signal quality values based on at least a portion of computed singular values.

44. The system according to claim 43, wherein said one or more circuits are operable to communicate, via said one or more uplink RF channels, said determined one or more signal quality values.

45. The system according to claim 44, wherein said one or more signal quality values are signal to noise ratios.

46. The system according to claim 35, wherein said rank value is greater than or equal to 1 and less than or equal to a minimum value selected from a number of transmitting antennas and a number of receiving antennas.