MIMO system with multiple spatial multiplexing modes

• US 9,031,097 B2
• Filed: 12/29/2009
• Issued: 05/12/2015
• Est. Priority Date: 10/25/2002
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Walton, J. Rodney, Ketchum, John W., Wallace, Mark S., Howard, Steven J.
• Primary Examiner(s): Hamza, Faruk
• Assistant Examiner(s): OH, ANDREW CHUNG SUK
• Application Number:
  US12/649,040
• Publication Number:
  US 20100119001A1
• Time in Patent Office: 1,960 Days
• Field of Search: None
• US Class Current: 370/535
• CPC Class Codes: H04B 7/0417 Feedback systems
• CPC Class Codes: H04B 7/0421 utilizing implicit feedback, e.g. steered pilot signals
• CPC Class Codes: H04B 7/043 using best eigenmode, e.g. beam forming or beam steering
• CPC Class Codes: H04B 7/0434 using multiple eigenmodes
• CPC Class Codes: H04B 7/0452 Multi-user MIMO systems
• CPC Class Codes: H04B 7/0628 Diversity capabilities
• CPC Class Codes: H04B 7/0669 using different channel coding between antennas space-time coding H04L1/0618
• CPC Class Codes: H04B 7/0689 using different transmission schemes, at least one of them being a diversity transmission scheme
• CPC Class Codes: H04B 7/0697 using spatial multiplexing
• CPC Class Codes: H04B 7/0854 using error minimizing algorithms, e.g. minimum mean squared error [MMSE], "cross-correlation" or matrix inversion
• CPC Class Codes: H04B 7/0871 using different reception schemes, at least one of them being a diversity reception scheme
• CPC Class Codes: H04J 11/003 at the transmitter transmission to multiple receive units in multiple input multiple output [MIMO] H04B7/0452; transmit antenna weighting H04B7/0615
• CPC Class Codes: H04J 11/0053 using co-ordinated multipoint transmission/reception co-ordinated antenna or beam-forming aspects H04B7/022
• CPC Class Codes: H04L 1/0001 Systems modifying transmission characteristics according to link quality, e.g. power backoff adaptive data allocation for multicarrier modulation H04L5/0044; controlling transmission power for radio systems H04W52/04
• 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 1/0017 where the mode-switching is based on Quality of Service requirement
• CPC Class Codes: H04L 1/06 using space diversity
• CPC Class Codes: H04L 25/0224 using sounding signals
• CPC Class Codes: H04L 25/0226 sounding signals per se
• CPC Class Codes: H04L 25/0242 : using matrix methods
• CPC Class Codes: H04L 25/0248 : Eigen-space methods
• CPC Class Codes: H04L 25/03343 : Arrangements at the transmitter end
• CPC Class Codes: H04L 25/03891 : Spatial equalizers MIMO diversity systems H04B7/0413
• CPC Class Codes: H04L 27/2601 : Multicarrier modulation systems
• CPC Class Codes: H04L 27/261 : Details of reference signals
• CPC Class Codes: H04L 27/2647 : Arrangements specific to the receiver only equalisation H04L27/01
• CPC Class Codes: H04L 27/2675 : Pilot or known symbols
• CPC Class Codes: H04L 5/0073 : Allocation arrangements that take into account other cell interferences for intercell interference mitigation or co-ordination in orthogonal multiplex systems H04J11/005
• CPC Class Codes: H04W 16/28 : using beam steering
• CPC Class Codes: H04W 52/50 : at the moment of starting communication in a multiple access environment
• CPC Class Codes: H04W 72/046 : the resource being in the space domain, e.g. beams
• CPC Class Codes: H04W 74/04 : Scheduled access hybrid access H04W74/02

Abstract

A MIMO system supports multiple spatial multiplexing modes for improved performance and greater flexibility. These modes may include (1) a single-user steered mode that transmits multiple data streams on orthogonal spatial channels to a single receiver, (2) a single-user non-steered mode that transmits multiple data streams from multiple antennas to a single receiver without spatial processing at a transmitter, (3) a multi-user steered mode that transmits multiple data streams simultaneously to multiple receivers with spatial processing at a transmitter, and (4) a multi-user non-steered mode that transmits multiple data streams from multiple antennas (co-located or non co-located) without spatial processing at the transmitter(s) to receiver(s) having multiple antennas. For each set of user terminal(s) selected for data transmission on the downlink and/or uplink, a spatial multiplexing mode is selected for the user terminal set from among the multiple spatial multiplexing modes supported by the system.

Claims

1. A method of transmitting data in a wireless multiple-input multiple-output (MIMO) communication system, comprising:

selecting a spatial multiplexing mode to use for data transmission from among a plurality of spatial multiplexing modes supported by the system based on whether a user terminal has performed calibration so that the user terminal can estimate a channel response for a downlink based on a pilot received via an uplink, the plurality of spatial multiplexing modes comprising at least one steered spatial multiplexing mode and a non-steered spatial multiplexing mode, wherein the steered spatial multiplexing mode includes spatial processing using eigenvectors of a channel response matrix for at least one subband;

coding and modulating a plurality of data streams in accordance with a plurality of rates to obtain a plurality of data symbol streams; and

using the spatial multiplexing mode, processing the plurality of data symbol streams to obtain a plurality of transmit symbol streams for transmission from a plurality of antennas.

2. The method of claim 1, wherein the selected spatial multiplexing mode is a steered spatial multiplexing mode, and wherein the plurality of data symbol streams are spatially processed with a plurality of steering vectors to transmit the plurality of data symbol streams on a plurality of orthogonal spatial channels of a MIMO channel.

3. The method of claim 2, further comprising:

transmitting a steered pilot on each of the plurality of orthogonal spatial channels.

4. The method of claim 1, wherein the plurality of data symbol streams are provided as the plurality of transmit symbol streams.

5. The method of claim 1, further comprising:

performing calibration so that uplink channel response is reciprocal of downlink channel response.

6. The method of claim 1, wherein:

each of the plurality of rates is selected from among a set of rates supported by the system.

7. An apparatus in a wireless multiple-input multiple-output (MIMO) communication system, comprising:

a controller operative to select a spatial multiplexing mode to use for data transmission from among a plurality of spatial multiplexing modes supported by the system based on whether a user terminal has performed calibration so that the user terminal can estimate a channel response for a downlink based on a pilot received via an uplink, the plurality of spatial multiplexing modes comprising at least one steered spatial multiplexing mode and a non-steered spatial multiplexing mode, wherein the steered spatial multiplexing mode includes spatial processing using eigenvectors of a channel response matrix for at least one subband;

a transmit data processor operative to code and modulate a plurality of data streams in accordance with a plurality of rates to obtain a plurality of data symbol streams; and

a transmit spatial processor operative to, using the spatial multiplexing mode, process the plurality of data symbol streams to obtain a plurality of transmit symbol streams for transmission from a plurality of antennas.

8. The apparatus of claim 7, wherein the selected spatial multiplexing mode is a steered spatial multiplexing mode, and wherein the plurality of data symbol streams are spatially processed with a plurality of steering vectors to transmit the plurality of data symbol streams on a plurality of orthogonal spatial channels of a MIMO channel.

9. The apparatus of claim 8, further comprising:

a transmitter operative to transmit a steered pilot on each of the plurality of orthogonal spatial channels.

10. The apparatus of claim 7, wherein the plurality of data symbol streams are provided as the plurality of transmit symbol streams.

11. The apparatus of claim 7, further comprising:

a calibrator operative to perform calibration so that uplink channel response is reciprocal of downlink channel response.

12. The apparatus of claim 7, wherein:

each of the plurality of rates is selected from among a set of rates supported by the system.

13. An apparatus of transmitting data in a wireless multiple-input multiple-output (MIMO) communication system, comprising:

means for selecting a spatial multiplexing mode to use for data transmission from among a plurality of spatial multiplexing modes supported by the system based on whether a user terminal has performed calibration so that the user terminal can estimate a channel response for a downlink based on a pilot received via an uplink, the plurality of spatial multiplexing modes comprising at least one steered spatial multiplexing mode and a non-steered spatial multiplexing mode, wherein the steered spatial multiplexing mode includes spatial processing using eigenvectors of a channel response matrix for at least one subband;

means for coding and modulating a plurality of data streams in accordance with a plurality of rates to obtain a plurality of data symbol streams; and

means for processing, using the spatial multiplexing mode, the plurality of data symbol streams to obtain a plurality of transmit symbol streams for transmission from a plurality of antennas.

14. The apparatus of claim 13, wherein the selected spatial multiplexing mode is a steered spatial multiplexing mode, and wherein the plurality of data symbol streams are spatially processed with a plurality of steering vectors to transmit the plurality of data symbol streams on a plurality of orthogonal spatial channels of a MIMO channel.

15. The apparatus of claim 14, further comprising:

means for transmitting a steered pilot on each of the plurality of orthogonal spatial channels.

16. The apparatus of claim 13, wherein the plurality of data symbol streams are provided as the plurality of transmit symbol streams.

17. The apparatus of claim 13, further comprising:

means for performing calibration so that uplink channel response is reciprocal of downlink channel response.

18. The apparatus of claim 13, wherein:

each of the plurality of rates is selected from among a set of rates supported by the system.

19. A non-transitory computer-readable medium for transmitting data in a wireless multiple-input multiple-output (MIMO) communication system, the computer-readable medium having a set of instructions stored thereon, the set of instructions being executable by one or more processors and the set of instructions comprising:

instructions for selecting a spatial multiplexing mode to use for data transmission from among a plurality of spatial multiplexing modes supported by the system based on whether a user terminal has performed calibration so that the user terminal can estimate a channel response for a downlink based on a pilot received via an uplink, the plurality of spatial multiplexing modes comprising at least one steered spatial multiplexing mode and a non-steered spatial multiplexing mode, wherein the steered spatial multiplexing mode includes spatial processing using eigenvectors of a channel response matrix for at least one subband;

instructions for coding and modulating a plurality of data streams in accordance with a plurality of rates to obtain a plurality of data symbol streams; and

instructions for processing, using the spatial multiplexing mode, the plurality of data symbol streams to obtain a plurality of transmit symbol streams for transmission from a plurality of antennas.

20. The computer-readable medium of claim 19, wherein the selected spatial multiplexing mode is a steered spatial multiplexing mode, and wherein the plurality of data symbol streams are spatially processed with a plurality of steering vectors to transmit the plurality of data symbol streams on a plurality of orthogonal spatial channels of a MIMO channel.

21. The computer-readable medium of claim 20, further comprising:

instructions for transmitting a steered pilot on each of the plurality of orthogonal spatial channels.

22. The computer-readable medium of claim 19, wherein the plurality of data symbol streams are provided as the plurality of transmit symbol streams.

23. The computer-readable medium of claim 19, further comprising:

instructions for performing calibration so that uplink channel response is reciprocal of downlink channel response.

24. The computer-readable medium of claim 19, wherein:

each of the plurality of rates is selected from among a set of rates supported by the system.

25. A method of receiving data in a wireless multiple-input multiple-output (MIMO) communication system, comprising:

receiving information indicating a spatial multiplexing mode to use for data transmission selected from among a plurality of spatial multiplexing modes supported by the system based on whether a user terminal has performed calibration so that the user terminal can estimate a channel response for a downlink based on a pilot received via an uplink, the plurality of spatial multiplexing modes comprising at least one steered spatial multiplexing mode and a non-steered spatial multiplexing mode, wherein the steered spatial multiplexing mode includes spatial processing using eigenvectors of a channel response matrix for at least one subband;

using the spatial multiplexing mode, processing at least one received symbol stream to obtain at least one recovered data symbol stream; and

demodulating and decoding the at least one recovered data symbol stream in accordance with at least one rate to obtain at least one decoded data stream.

26. The method of claim 25, wherein the selected spatial multiplexing mode is a steered spatial multiplexing mode, and wherein a plurality of received symbol streams are spatially processed with a plurality of eigenvectors for a plurality of spatial channels of a MIMO channel to obtain a plurality of recovered data symbol streams.

27. The method of claim 25, wherein a plurality of received symbol streams are spatially processed based on a channel correlation matrix inversion (CCMI) technique, a minimum mean square error (MMSE) technique, or a successive interference cancellation (SIC) technique to obtain a plurality of recovered data symbol streams.

28. The method of claim 25, wherein one received symbol stream is processed with channel gain estimates to obtain one recovered data symbol stream.

29. The method of claim 25, wherein:

each of the at least one rate is selected from among a set of rates supported by the system.

30. An apparatus in a wireless multiple-input multiple-output (MIMO) communication system, comprising:

a controller operative to receive information indicating a spatial multiplexing mode to use for data transmission selected from among a plurality of spatial multiplexing modes supported by the system based on whether a user terminal has performed calibration so that the user terminal can estimate a channel response for a downlink based on a pilot received via an uplink, the plurality of spatial multiplexing modes comprising at least one steered spatial multiplexing mode and a non-steered spatial multiplexing mode, wherein the steered spatial multiplexing mode includes spatial processing using eigenvectors of a channel response matrix for at least one subband;

a receive spatial processor operative to, using the spatial multiplexing mode, process at least one received symbol stream to obtain at least one recovered data symbol stream; and

a receive data processor operative to demodulate and decode the at least one recovered data symbol stream in accordance with at least one rate to obtain at least one decoded data stream.

31. The apparatus of claim 30, wherein the selected spatial multiplexing mode is a steered spatial multiplexing mode, and wherein a plurality of received symbol streams are spatially processed with a plurality of eigenvectors for a plurality of spatial channels of a MIMO channel to obtain a plurality of recovered data symbol streams.

32. The apparatus of claim 30, wherein a plurality of received symbol streams are spatially processed based on a channel correlation matrix inversion (CCMI) technique, a minimum mean square error (MMSE) technique, or a successive interference cancellation (SIC) technique to obtain a plurality of recovered data symbol streams.

33. The apparatus of claim 30, wherein one received symbol stream is processed with channel gain estimates to obtain one recovered data symbol stream.

34. The apparatus of claim 30, wherein:

each of the at least one rate is selected from among a set of rates supported by the system.

35. An apparatus of receiving data in a wireless multiple-input multiple-output (MIMO) communication system, comprising:

means for receiving information indicating a spatial multiplexing mode to use for data transmission selected from among a plurality of spatial multiplexing modes supported by the system based on whether a user terminal has performed calibration so that the user terminal can estimate a channel response for a downlink based on a pilot received via an uplink, the plurality of spatial multiplexing modes comprising at least one steered spatial multiplexing mode and a non-steered spatial multiplexing mode, wherein the steered spatial multiplexing mode includes spatial processing using eigenvectors of a channel response matrix for at least one subband;

means for processing, using the spatial multiplexing mode, at least one received symbol stream to obtain at least one recovered data symbol stream; and

means for demodulating and decoding the at least one recovered data symbol stream in accordance with at least one rate to obtain at least one decoded data stream.

36. The apparatus of claim 35, wherein the selected spatial multiplexing mode is a steered spatial multiplexing mode, and wherein a plurality of received symbol streams are spatially processed with a plurality of eigenvectors for a plurality of spatial channels of a MIMO channel to obtain a plurality of recovered data symbol streams.

37. The apparatus of claim 35, wherein a plurality of received symbol streams are spatially processed based on a channel correlation matrix inversion (CCMI) technique, a minimum mean square error (MMSE) technique, or a successive interference cancellation (SIC) technique to obtain a plurality of recovered data symbol streams.

38. The apparatus of claim 35, wherein one received symbol stream is processed with channel gain estimates to obtain one recovered data symbol stream.

39. The apparatus of claim 35, wherein:

each of the at least one rate is selected from among a set of rates supported by the system.

40. A non-transitory computer-readable medium for receiving data in a wireless multiple-input multiple-output (MIMO) communication system, the computer-readable medium having a set of instructions stored thereon, the set of instructions being executable by one or more processors and the set of instructions comprising:

instructions for receiving information indicating a spatial multiplexing mode to use for data transmission selected from among a plurality of spatial multiplexing modes supported by the system based on whether a user terminal has performed calibration so that the user terminal can estimate a channel response for a downlink based on a pilot received via an uplink, the plurality of spatial multiplexing modes comprising at least one steered spatial multiplexing mode and a non-steered spatial multiplexing mode, wherein the steered spatial multiplexing mode includes spatial processing using eigenvectors of a channel response matrix for at least one subband;

instructions for processing, using the spatial multiplexing mode, at least one received symbol stream to obtain at least one recovered data symbol stream; and

instructions for demodulating and decoding the at least one recovered data symbol stream in accordance with at least one rate to obtain at least one decoded data stream.

41. The computer-readable medium of claim 40, wherein the selected spatial multiplexing mode is a steered spatial multiplexing mode, and wherein a plurality of received symbol streams are spatially processed with a plurality of eigenvectors for a plurality of spatial channels of a MIMO channel to obtain a plurality of recovered data symbol streams.

42. The computer-readable medium of claim 40, wherein a plurality of received symbol streams are spatially processed based on a channel correlation matrix inversion (CCMI) technique, a minimum mean square error (MMSE) technique, or a successive interference cancellation (SIC) technique to obtain a plurality of recovered data symbol streams.

43. The computer-readable medium of claim 40, wherein one received symbol stream is processed with channel gain estimates to obtain one recovered data symbol stream.

44. The computer-readable medium of claim 40, wherein:

each of the at least one rate is selected from among a set of rates supported by the system.