Method and system for rate selection algorithm to maximize throughput in closed loop multiple input multiple output (MIMO) wireless local area network (WLAN) system

• US 20060159120A1
• Filed: 02/18/2005
• Published: 07/20/2006
• 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 7,525,988 B2
• Time in Patent Office: Days
• US Class Current: 370/465
• 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. A method for communicating information in a communication system, the method comprising:

computing a maximum number of binary bits to be simultaneously transmitted via at least one of a plurality of RF channels based on a signal quality of at least one of a plurality of received RF channels;

selecting a modulation technique based on said computed maximum number of binary bits;

communicating, via one of said at least one of said plurality of RF channels and an uplink channel, feedback information comprising said selected said modulation technique; and

receiving, via said at least one of said plurality of received RF channels, subsequently transmitted data that is modulated based on said feedback information.

2. The method according to claim 1, wherein said computed maximum number of binary bits is determined based on at least a packet error rate of said at least one of said plurality of received RF channels.

3. The method according to claim 1, further comprising determining a range of said modulation technique and coding rate combinations based on at least one signal to noise ratio.

4. The method according to claim 3, further comprising representing said modulation technique and coding rate combinations and said at least one signal to noise ratio in a lookup table.

5. The method according to claim 3, further comprising selecting at least one of said modulation technique and said coding rate combinations based on at least a packet error rate.

6. The method according to claim 5, further comprising communicating said feedback information comprising said selected at least one of said modulation technique and said coding rate via said one of said at least one of said plurality of RF channels and said uplink channel.

7. The method according to claim 1, wherein said signal quality comprises a signal to noise ratio.

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

a receive demodulation control processor that computes a maximum number of binary bits to be simultaneously transmitted via at least one of a plurality of RF channels based on a signal quality of at least one of a plurality of received RF channels;

said receive demodulation control processor selects a modulation technique based on said computed maximum number of binary bits;

at least one transmitting antenna front end that communicates, via one of said at least one of said plurality of RF channels and an uplink channel, feedback information comprising said selected said modulation technique; and

at least one receiving antenna front end that receives, via said at least one of said plurality of received RF channels, subsequently transmitted data that is modulated based on said feedback information.

9. The system according to claim 8, wherein said computed maximum number of binary bits is determined based on at least a packet error rate of said at least one of said plurality of received RF channels.

10. The system according to claim 8, further comprising at least one processor that determines a range of said modulation technique and coding rate combinations based on at least one signal to noise ratio.

11. The system according to claim 10, wherein said at least one processor represents said modulation technique and coding rate combinations and said at least one signal to noise ratio in a lookup table.

12. The system according to claim 10, wherein said at least one processor selects at least one of said modulation technique and said coding rate combinations based on at least a packet error rate.

13. The system according to claim 12, wherein said transmitting antenna front end communicates said feedback information comprising said selected at least one of said modulation technique and said coding rate via said one of said at least one of said plurality of RF channels and said uplink channel.

14. The system according to claim 8, wherein said signal quality comprises a signal to noise ratio.

15. A method for communicating information in a multiple input multiple output communication system, the method comprising:

receiving via one of a plurality of received RF channels and an uplink channel, feedback information comprising at least one of a selected modulation technique and coding rate; and

transmitting subsequent data via said plurality of RF channels which is at least one of modulated and coded based on said feedback information.

16. The method according to claim 15, further comprising selecting a modulation technique based on at least one of a computed maximum number of binary bits to be simultaneously transmitted via said plurality of RF channels and at least one packet error rate, at least one computed throughput rate, and at least one signal to noise ratio of one of said uplink channel and a downlink channel.

17. The method according to claim 15, further comprising determining a range of modulation technique and coding rate combinations based on at least one packet error rate, at least one computed throughput rate, and at least one signal to noise ratio of one of said uplink channel, and a downlink channel.

18. The method according to claim 17, further comprising communicating information via one of said plurality of RF channels and a downlink channel comprising a selected at least one of said modulation technique and coding rate.

19. A system for communicating information in a multiple input multiple output communication system, the system comprising:

at least one receiving antenna front end that receives feedback information comprising at least one of a selected modulation technique and coding rate via one of a plurality of received RF channels and an uplink channel; and

at least one transmitting antenna front end that transmits, via said plurality of RF channels, subsequent data that is at least one of modulated and coded based on said feedback information.

20. The system according to claim 19, further comprising a transmit modulation control processor that selects a modulation technique based on at least one of a computed maximum number of binary bits to be simultaneously transmitted via said plurality of RF channels and at least one packet error rate, at least one computed throughput rate, and at least one signal to noise ratio of said uplink channel and a downlink channel.

21. The system according to claim 19, further comprising at least one processor that determines a range of modulation technique and coding rate combinations based on at least one packet error rate, at least one computed throughput rate, and at least one signal to noise ratio of one of said uplink channel and a downlink channel.

22. The system according to claim 21, wherein said transmitting antenna front end communicates information via one of, said plurality of RF channels, and a downlink channel comprising a selected at least one of said modulation technique and coding rate.