MIMO decoding in the presence of various interfering sources

• US 8,611,452 B1
• Filed: 03/23/2012
• Issued: 12/17/2013
• Est. Priority Date: 09/11/2007
• Status: Active Grant

• Current Assignee: Marvell Asia Pte Limited (Marvell Technology Group Limited)
• Original Assignee: Marvell International Limited (Marvell Technology Group Limited)
• Inventors: Lee, Jungwon, Nabar, Rohit U.
• Primary Examiner(s): Ahn, Sam K
• Assistant Examiner(s): Haider, Syed
• Application Number:
  US13/428,728
• Time in Patent Office: 634 Days
• Field of Search: 375/219, 375/260, 375/267, 375/295, 375/298, 375/299, 375/340, 375/341, 375/346, 375/347, 375/348, 375/350, 370/203, 370/208, 370/210, 370/231, 370/319, 370/328, 370/337, 455/69, 455/70, 455/296, 455/450, 455/454, 455/500, 455/501, 455/562.1
• US Class Current: 375/267
• CPC Class Codes: H04B 7/0413 MIMO systems
• CPC Class Codes: H04L 1/0048 in conjunction with detection of multiuser or interfering signals, e.g. iteration between CDMA or MIMO detector and FEC decoder for spatial equalizer H04L25/03286
• CPC Class Codes: H04L 1/0631 Receiver arrangements
• CPC Class Codes: H04L 2025/03426 transmission using multiple-input and multiple-output channels
• CPC Class Codes: H04L 25/0204 of multiple channels
• CPC Class Codes: H04L 5/0023 Time-frequency-space

Abstract

A method includes obtaining a first set of one or more parameters associated with a plurality of transmitters transmitting a plurality of intended streams and obtaining a second set of one or more parameters associated with an interference source. The first set of parameters includes a first MIMO mode associated with the plurality of transmitters and the second set of parameters includes a second MIMO mode associated with the interference source. The method also includes receiving a plurality of streams, including the plurality of intended streams and a plurality of interfering streams transmitted by the interference source, and selecting a pre-processing scheme based at least in part on the first MIMO mode and the second MIMO mode.

Claims

1. A method for processing signals received via multiple input multiple output (MIMO) communication channels, the method comprising:

obtaining a first set of one or more parameters associated with a plurality of transmitters transmitting a plurality of intended streams, wherein the first set of one or more parameters includes a first MIMO mode associated with the plurality of transmitters;

obtaining a second set of one or more parameters associated with an interference source, wherein the second set of one or more parameters includes a second MIMO mode associated with the interference source;

receiving a plurality of streams including (i) the plurality of intended streams and (ii) a plurality of interfering streams transmitted by the interference source;

selecting a pre-processing scheme based at least in part on the first MIMO mode and the second MIMO mode, wherein selecting the pre-processing scheme includes

selecting a first equivalent receive signal model if (i) the first MIMO mode indicates that the plurality of intended streams is space-time coded and (ii) the second MIMO mode indicates that the plurality of interfering streams is space-time coded,

selecting a second equivalent receive signal model if (i) the first MIMO mode indicates that the plurality of intended streams is space-time coded and (ii) the second MIMO mode indicates that the plurality of interfering streams is not space-time coded, and

selecting a third equivalent receive signal model if (i) the first MIMO mode indicates that the plurality of intended streams is not space-time coded and (ii) the second MIMO mode indicates that the plurality of interfering streams is space-time coded; and

demodulating the plurality of streams.

2. The method of claim 1, wherein:

the second set of one or more parameters includes at least one of (i) a modulation scheme or (ii) channel gain information; and

demodulating the plurality of streams is based in part on the second set of one or more parameters.

3. A communication device comprising:

a receiver configured to

obtain a first set of one or more parameters associated with a plurality of transmitters transmitting a plurality of intended streams, wherein the first set of one or more parameters includes a first MIMO mode associated with the plurality of transmitters,

obtain a second set of one or more parameters associated with an interference source, wherein the second set of one or more parameters includes a second MIMO mode associated with the interference source,

receive a plurality of streams including (i) the plurality of intended streams and (ii) a plurality of interfering streams transmitted by the interference source,

select a pre-processing scheme based at least in part on the first MIMO mode and the second MIMO mode, wherein the receiver is configured to

select a first equivalent receive signal model if (i) the first MIMO mode indicates that the plurality of intended streams is space-time coded and (ii) the second MIMO mode indicates that the plurality of interfering streams is space-time coded,

select a second equivalent receive signal model if (i) the first MIMO mode indicates that the plurality of intended streams is space-time coded and (ii) the second MIMO mode indicates that the plurality of interfering streams is not space-time coded, and

select a third equivalent receive signal model if (i) the first MIMO mode indicates that the plurality of intended streams is not space-time coded and (ii) the second MIMO mode indicates that the plurality of interfering streams is space-time coded, and

demodulate the plurality of streams.

4. The communication device of claim 3, wherein:

the second set of one or more parameters includes at least one of (i) a modulation scheme or (ii) channel gain information; and

the receiver is configured to demodulate the plurality of streams based in part on the second set of one or more parameters.

5. The communication device of claim 3, wherein the receiver is configured to:

receive the plurality of streams at least in part by receiving the plurality of streams at a plurality of antennas; and

demodulate the plurality of streams at least in part by using a plurality of noise parameters, wherein each of the plurality of noise parameters corresponds to a respective one of the plurality of antennas.

6. The communication device of claim 3, wherein:

the interference source includes an additional plurality of transmitters; and

the plurality of transmitters and the additional plurality of transmitters are associated with respective cells of a cellular communication network.

7. The communication device of claim 6, wherein the cellular communication network is compliant with the Institute for Electrical and Electronics Engineers (IEEE) 802.16 Standard.

8. The communication device of claim 3, wherein:

the plurality of transmitters are antennas associated with a first base station;

the interference source includes a plurality of antennas associated with a second base station;

the intended streams are downlink streams from the first base station to a mobile station; and

the receiver is configured to obtain the second set of parameters associated with the interference source at least in part by processing channel data associated with the second base station.

9. The communication device of claim 8, wherein the receiver is configured to obtain the second set of parameters associated with the interference source at least in part by processing a downlink map (DL-MAP) message.

10. The communication device of claim 8, wherein the receiver is configured to obtain the second set of parameters associated with the interference source at least in part by processing a pseudo-noise (PN) sequence transmitted at a pilot sub-carrier from the second base station.

11. The communication device of claim 3, wherein:

the plurality of transmitters is associated with at least a first mobile station;

the interference source is associated with at least a second mobile station;

the intended streams are uplink streams from the first mobile station to a first base station; and

the receiver is configured to obtain the second set of parameters associated with the interference source at least in part by processing channel data associated with at least a second base station adjacent to the first base station.

12. The communication device of claim 11, wherein the receiver is configured to obtain the second set of parameters at least in part by receiving the second set of parameters via a backbone network to which the first base station and the second base station are communicatively coupled.

13. The communication device of claim 3, wherein the receiver is configured to demodulate the plurality of streams at least in part by calculating a log-likelihood ratio (LLR) for each symbol in the plurality of intended streams according to a maximum-likelihood (ML) scheme.

14. The communication device of claim 13, wherein the receiver is configured to calculate the LLR based on performing QR decomposition of a channel matrix corresponding to a channel including the plurality of intended streams and the plurality of interfering streams.

15. The communication device of claim 3, wherein:

the receiver is configured to demodulate the pre-processed plurality of streams at least in part by calculating a log-likelihood ratio (LLR) for each symbol in the plurality of intended streams; and

the receiver is further configured to equalize a subset of streams within the plurality of streams prior to LLR calculation.