Method and system for low complexity conjugate gradient based equalization in a wireless system

• US 8,891,606 B2
• Filed: 12/31/2012
• Issued: 11/18/2014
• Est. Priority Date: 10/06/2004
• Status: Active Grant

• Current Assignee: Avago Technologies International Sales Pte Limited (Broadcom, Inc.)
• Original Assignee: Broadcom Corporation (Broadcom, Inc.)
• Inventors: Kent, Mark, Landau, Uri, Catreux-Erceg, Severine, Erceg, Vinko, Kong, Ning, Roux, Pieter
• Primary Examiner(s): WANG, TED M
• Application Number:
  US13/732,047
• Publication Number:
  US 20130128945A1
• Time in Patent Office: 687 Days
• Field of Search: 375/232, 375/229, 375/233, 375/316, 375/346, 375/348, 375/350
• US Class Current: 375/232
• CPC Class Codes: H04B 7/0413 MIMO systems
• CPC Class Codes: H04L 2025/03426 transmission using multiple-input and multiple-output channels
• CPC Class Codes: H04L 2025/03471 Tapped delay lines H04L2025/03464 takes precedence
• CPC Class Codes: H04L 2025/03617 Time recursive algorithms H04L2025/03643 takes precedence
• CPC Class Codes: H04L 2025/03662 to a fixed value
• CPC Class Codes: H04L 2025/037 Detection of convergence state
• CPC Class Codes: H04L 25/03038 with a non-recursive structure H04L25/03031 takes precedence

Abstract

Methods and systems for processing signals in a receiver are disclosed herein and may include updating a plurality of filter taps utilizing at least one channel response vector and at least one correlation vector, for a plurality of received clusters, based on initialized values related to the at least one channel response vector and the at least one correlation vector. At least a portion of the received signal clusters may be filtered utilizing at least a portion of the updated plurality of filter taps. The update may be repeated whenever a specified signal-to-noise ratio (SNR) for the received signal clusters is reached. The initialized values may be updated during a plurality of iterations, and the update may be repeated whenever a specified number of the plurality of iterations is reached.

Claims

1. A method for processing wireless signals, comprising:

receiving first and second wireless signals comprising information transmitted from one or more transmit antennas;

generating a correlation vector that corresponds to said first wireless signal correlated with a complex conjugate of said second wireless signal; and

updating an equalizer tap according to said correlation vector upon determining that a signal-to-noise ratio (SNR) requirement is satisfied.

2. The method of claim 1, further comprising generating said equalizer tap according to a channel response vector that corresponds to the combination of a receive antenna and a transmit antenna.

3. The method of claim 1, wherein said equalizer tap is updated iteratively while the SNR requirement is satisfied.

4. The method of claim 1, wherein said equalizer tap is updated a pre-determined number of times.

5. The method of claim 1, further comprising generating a chip-rate synchronously sampled signal based on a chip clocking signal and at least one of said first and second wireless signals.

6. The method of claim 5, further comprising generating a received signal estimate based on said generated chip-rate synchronously sampled signal.

7. The method of claim 5, wherein the correlation vector is generated using the chip-rate synchronously sampled signal.

8. The method of claim 1, wherein said first and second wireless signals comprise a signal cluster.

9. The method of claim 1, wherein said equalizer tap is updated according to a conjugate gradient based on said correlation vector.

10. The method of claim 1, wherein said SNR requirement is determined to be satisfied when said SNR falls within a predetermined range.

11. A system for processing wireless signals, comprising:

one or more receive ports configured to receive first and second wireless signals comprising information transmitted from one or more transmit antennas;

a correlator configured to generate a correlation vector that corresponds to said first wireless signal correlated with a complex conjugate of said second wireless signal; and

a conjugate gradiant tap optimizer (CGTO) configured to update an equalizer tap according to said correlation vector upon determining that a signal-to-noise ratio (SNR) requirement is satisfied.

12. The system of claim 11, wherein said CGTO is configured to generate said equalizer tap according to a channel response vector that corresponds to the combination of a receive antenna and a transmit antenna.

13. The system of claim 11, wherein said CGTO is configured to update said equalizer tap iteratively while the SNR requirement is satisfied.

14. The system of claim 11, wherein said CGTO is configured to update said equalizer tap a pre-determined number of times.

15. The system of claim 11, wherein said correlator is configured to generate a chip-rate synchronously sampled signal based on a chip clocking signal and at least one of said first and second wireless signals.

16. The system of claim 15, wherein said correlator is configured to generate a received signal estimate based on said generated chip-rate synchronously sampled signal.

17. The system of claim 15, wherein said correlator is configured to generate said correlation vector using the chip-rate synchronously sampled signal.

18. The system of claim 11, wherein said first and second wireless signals comprise a signal cluster.

19. The system of claim 11, wherein said CGTO is configured to update said equalizer tap according to a conjugate gradient based on said correlation vector.

20. The method of claim 11, wherein said CGTO is configured to determine that said SNR requirement is satisfied when said SNR falls within a predetermined range.