Method and system for adaptive modulations and signal field for closed loop multiple input multiple output (MIMO) wireless local area network (WLAN) system

• US 8,077,669 B2
• Filed: 11/23/2010
• Issued: 12/13/2011
• Est. Priority Date: 02/07/2005
• Status: Active Grant

• Current Assignee: Broadcom Corporation (Broadcom, Inc.)
• Original Assignee: Broadcom Corporation (Broadcom, Inc.)
• Inventors: Kim, Joonsuk
• Primary Examiner(s): Moe, Aung S
• Assistant Examiner(s): ROSE, KERRI M
• Application Number:
  US12/952,275
• Publication Number:
  US 20110069778A1
• Time in Patent Office: 385 Days
• Field of Search: 370/310, 370/328, 370/329, 370/340, 370/341, 370/464, 370/465, 455/422.1, 455/445, 455/450, 455/451, 455/452.1, 455/452.2
• US Class Current: 370/329
• CPC Class Codes: H04B 7/024 Co-operative use of antennas of several sites, e.g. in co-ordinated multipoint or co-operative multiple-input multiple-output [MIMO] systems
• CPC Class Codes: H04B 7/0413 MIMO 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 1/0026 Transmission of channel quality indication
• CPC Class Codes: H04L 1/0618 Space-time coding
• CPC Class Codes: H04L 1/0693 Partial feedback, e.g. partial channel state information [CSI]
• CPC Class Codes: H04L 25/0224 using sounding signals
• CPC Class Codes: H04L 27/0008 arrangements for allowing a transmitter or receiver to use more than one type of modulation negotiating modulation type for two-way transmission paths H04L5/1453
• CPC Class Codes: H04L 27/0012 arrangements for identifying the type of modulation
• CPC Class Codes: H04L 27/2613 Structure of the reference signals
• CPC Class Codes: H04L 5/0023 Time-frequency-space
• CPC Class Codes: H04L 5/0042 intra-user or intra-terminal allocation
• CPC Class Codes: H04L 5/0046 Determination of how many bits are transmitted on different sub-channels
• CPC Class Codes: H04L 5/006 Quality of the received signal, e.g. BER, SNR, water filling
• CPC Class Codes: H04L 5/0094 Indication of how sub-channels of the path are allocated

Abstract

A method for communicating information is disclosed and includes, in a multiple-input-multiple-output (MIMO) communication system utilizing a plurality of modulation types and a plurality of spatial streams, determining an aggregate noise characteristic based upon a noise characteristic of each of the plurality of spatial streams. A receiver may be configured to receive subsequent data based on one or both of: a current modulation type for modulating a current spatial stream and at least one subsequent modulation type for modulating at least one subsequent spatial stream. The current modulation type and the at least one subsequent modulation type may be based on the determined aggregate noise characteristic. A constellation field may be encoded to uniquely identify a combination comprising the current modulation type, and the at least one subsequent modulation type.

Claims

1. A method for communicating information in a communications system, the method comprising:

in a multiple-input-multiple-output (MIMO) communication system utilizing a plurality of modulation types and a plurality of spatial streams,

determining an aggregate noise characteristic based upon a noise characteristic of each of said plurality of spatial streams; and

configuring a receiver to receive subsequent data based on one or both of;

a current modulation type for modulating a current spatial stream and at least one subsequent modulation type for modulating at least one subsequent spatial stream,

wherein said current modulation type and said at least one subsequent modulation type are based on said determined aggregate noise characteristic.

2. The method according to claim 1, comprising encoding a constellation field to uniquely identify a combination comprising said current modulation type, and said at least one subsequent modulation type.

3. The method according to claim 1, wherein said at least one subsequent modulation type comprises a number of constellation points that is less than or equal to a number of constellation points in said current modulation type.

4. The method according to claim 1, comprising selecting one or both of:

said current modulation type and said at least one subsequent modulation type, based on said determined aggregate noise characteristic.

5. The method according to claim 1, wherein said determined aggregate noise characteristic comprises at least one signal-to-noise ratio (SNR).

6. A system for communicating information in a communications system, the system comprising:

circuitry for use in a multiple-input-multiple-output (MIMO) communication system utilizing a plurality of modulation types and a plurality of spatial streams, said circuitry operable to determine an aggregate noise characteristic based upon a noise characteristic of each of said plurality of spatial streams; and

said circuitry operable to configure a receiver to receive subsequent data based on one or both of;

a current modulation type for modulating a current spatial stream and at least one subsequent modulation type for modulating at least one subsequent spatial stream,

wherein said current modulation type and said at least one subsequent modulation type are based on said determined aggregate noise characteristic.

7. The system according to claim 6, wherein said circuitry is operable to encode a constellation field to uniquely identify a combination comprising said current modulation type, and said at least one subsequent modulation type.

8. The system according to claim 6, wherein said at least one subsequent modulation type comprises a number of constellation points that is less than or equal to a number of constellation points in said current modulation type.

9. The system according to claim 6, wherein said circuitry is operable to select one or both of:

said current modulation type and said at least one subsequent modulation type, based on said determined aggregate noise characteristic.

10. The system according to claim 6, wherein said determined aggregate noise characteristic comprises at least one signal-to-noise ratio (SNR).

11. A method for communicating information in a communications system, the method comprising:

in a multiple-input-multiple-output (MIMO) communication system utilizing a plurality of modulation types and a plurality of spatial streams,

determining an aggregate noise characteristic based upon a noise characteristic of each of said plurality of spatial streams; and

configuring a transmitter to transmit subsequent data based on one or both of;

a current modulation type for modulating a current spatial stream and at least one subsequent modulation type for modulating at least one subsequent spatial stream,

wherein said current modulation type and said at least one subsequent modulation type are based on said determined aggregate noise characteristic.

12. The method according to claim 11, comprising encoding a constellation field to uniquely identify a combination comprising said current modulation type, and said at least one subsequent modulation type.

13. The method according to claim 11, wherein said at least one subsequent modulation type comprises a number of constellation points that is less than or equal to a number of constellation points in said current modulation type.

14. The method according to claim 11, comprising selecting one or both of:

said current modulation type and said at least one subsequent modulation type, based on said determined aggregate noise characteristic.

15. The method according to claim 11, wherein said determined aggregate noise characteristic comprises at least one signal-to-noise ratio (SNR).

16. A system for communicating information in a communications system, the system comprising:

circuitry for use in a multiple-input-multiple-output (MIMO) communication system utilizing a plurality of modulation types and a plurality of spatial streams, said circuitry operable to determine an aggregate noise characteristic based upon a noise characteristic of each of said plurality of spatial streams; and

said circuitry operable to configure a transmitter to transmit subsequent data based on one or both of;

a current modulation type for modulating a current spatial stream and at least one subsequent modulation type for modulating at least one subsequent spatial stream,

wherein said current modulation type and said at least one subsequent modulation type are based on said determined aggregate noise characteristic.

17. The system according to claim 16, wherein said circuitry is operable to encode a constellation field to uniquely identify a combination comprising said current modulation type, and said at least one subsequent modulation type.

18. The system according to claim 16, wherein said at least one subsequent modulation type comprises a number of constellation points that is less than or equal to a number of constellation points in said current modulation type.

19. The system according to claim 16, wherein said circuitry is operable to select one or both of:

said current modulation type and said at least one subsequent modulation type, based on said determined aggregate noise characteristic.

20. The system according to claim 16, wherein said determined aggregate noise characteristic comprises at least one signal-to-noise ratio (SNR).

21. A method for communicating information in a communications system, the method comprising:

in a multiple-input-multiple-output (MIMO) communication system utilizing a plurality of modulation types and a plurality of spatial streams,

determining an aggregate power characteristic based upon a power characteristic of each of said plurality of spatial streams; and

configuring a receiver to receive subsequent data based on one or both of;

a current modulation type for modulating a current spatial stream and at least one subsequent modulation type for modulating at least one subsequent spatial stream,

wherein said current modulation type and said at least one subsequent modulation type are based on said determined aggregate power characteristic.

22. The method according to claim 21, comprising encoding a constellation field to uniquely identify a combination comprising said current modulation type, and said at least one subsequent modulation type.

23. The method according to claim 21, wherein said at least one subsequent modulation type comprises a number of constellation points that is less than or equal to a number of constellation points in said current modulation type.

24. The method according to claim 21, comprising selecting one or both of:

said current modulation type and said at least one subsequent modulation type, based on said determined aggregate power characteristic.

25. A system for communicating information in a communications system, the system comprising:

circuitry for use in a multiple-input-multiple-output (MIMO) communication system utilizing a plurality of modulation types and a plurality of spatial streams, said circuitry operable to determine an aggregate power characteristic based upon a power characteristic of each of said plurality of spatial streams; and

said circuitry operable to configure a receiver to receive subsequent data based on one or both of;

a current modulation type for modulating a current spatial stream and at least one subsequent modulation type for modulating at least one subsequent spatial stream,

wherein said current modulation type and said at least one subsequent modulation type are based on said determined aggregate power characteristic.

26. The system according to claim 25, wherein said circuitry is operable to encode a constellation field to uniquely identify a combination comprising said current modulation type, and said at least one subsequent modulation type.

27. The system according to claim 25, wherein said at least one subsequent modulation type comprises a number of constellation points that is less than or equal to a number of constellation points in said current modulation type.

28. The system according to claim 25, wherein said circuitry is operable to select one or both of:

said current modulation type and said at least one subsequent modulation type, based on said determined aggregate power characteristic.

29. A method for communicating information in a communications system, the method comprising:

in a multiple-input-multiple-output (MIMO) communication system utilizing a plurality of modulation types and a plurality of spatial streams,

determining an aggregate power characteristic based upon a power characteristic of each of said plurality of spatial streams; and

configuring a transmitter to transmit subsequent data based on one or both of;

a current modulation type for modulating a current spatial stream and at least one subsequent modulation type for modulating at least one subsequent spatial stream,

wherein said current modulation type and said at least one subsequent modulation type are based on said determined aggregate power characteristic.

30. The method according to claim 29, comprising encoding a constellation field to uniquely identify a combination comprising said current modulation type, and said at least one subsequent modulation type.

31. The method according to claim 29, wherein said at least one subsequent modulation type comprises a number of constellation points that is less than or equal to a number of constellation points in said current modulation type.

32. The method according to claim 29, comprising selecting one or both of:

said current modulation type and said at least one subsequent modulation type, based on said determined aggregate power characteristic.

33. A system for communicating information in a communications system, the system comprising:

circuitry for use in a multiple-input-multiple-output (MIMO) communication system utilizing a plurality of modulation types and a plurality of spatial streams, said circuitry operable to determine an aggregate power characteristic based upon a power characteristic of each of said plurality of spatial streams; and

said circuitry operable to configure a transmitter to transmit subsequent data based on one or both of;

a current modulation type for modulating a current spatial stream and at least one subsequent modulation type for modulating at least one subsequent spatial stream,

wherein said current modulation type and said at least one subsequent modulation type are based on said determined aggregate power characteristic.

34. The system according to claim 33, wherein said circuitry is operable to encode a constellation field to uniquely identify a combination comprising said current modulation type, and said at least one subsequent modulation type.

35. The system according to claim 33, wherein said at least one subsequent modulation type comprises a number of constellation points that is less than or equal to a number of constellation points in said current modulation type.

36. The system according to claim 33, wherein said circuitry is operable to select one or both of:

said current modulation type and said at least one subsequent modulation type, based on said determined aggregate power characteristic.