Reduced complexity sliding window based equalizer

• US 20060034398A1
• Filed: 11/03/2005
• Published: 02/16/2006
• Est. Priority Date: 03/03/2003
• Status: Abandoned Application

• Current Assignee: Interdigital Technology Corporation (InterDigital, Inc.)
• Original Assignee: Interdigital Technology Corporation (InterDigital, Inc.)
• Inventors: Yang, Rui, Reznik, Alexander, Zeira, Ariela, Li, Bin
• Application Number:
  US11/265,932
• Publication Number:
  US 20060034398A1
• Time in Patent Office: Days
• US Class Current: 375/340
• CPC Class Codes: H04B 1/71052 using decorrelation matrix
• CPC Class Codes: H04L 2025/03426 transmission using multiple-input and multiple-output channels
• CPC Class Codes: H04L 2025/03509 fractionally spaced H04L2025/03515 takes precedence
• CPC Class Codes: H04L 2025/03605 Block algorithms
• CPC Class Codes: H04L 25/0212 of impulse response
• CPC Class Codes: H04L 25/0242 using matrix methods
• CPC Class Codes: H04L 25/03057 with a recursive structure H04L25/03031 takes precedence
• CPC Class Codes: H04L 25/03292 with channel estimation circuitry

Abstract

Data estimation is performed in a wireless communication system using both oversampling and multiple reception antennas. A receive vector is produced for each antenna at a sampling interval which is a multiple of the chip rate of the received signal. A channel response matrix is produced for each antenna at a preferred multiple of the sampling rate. Each receive vector is processed using a sliding window based approach, where a plurality of successive windows are processed. For each window, a combined circulant channel response matrix is produced using the channel response matrices. Using the combined circulant channel response matrix and a combined received vector comprising each received vector in a discrete Fourier transform based approach to estimate a data vector corresponding to that window; and combining the data vector estimated in each window to form a combined data vector.

Claims

1. A method for data estimation in a wireless communications system for a receiver using multiple chip rate sampling and multiple receive antennas, the method comprising:

producing a received vector at the sampling rate for each receive antenna;

producing a channel response matrix for each antenna at a preferred rate which is slower than the sampling rate;

processing each received vector using a sliding window based approach, where a plurality of successive windows are processed;

for each window of the plurality of windows;

producing a combined circulant channel response matrix using the channel response matrices; and

using the combined circulant channel response matrix and a combined received vector comprising each received vector in a discrete Fourier transform based approach for estimating a data vector corresponding to that window; and

combining the data vector estimated in each window to form a combined data vector.

2. The method of claim 1 wherein the sliding window based approach uses an exact solution.

3. The method of claim 1 wherein the sliding window based approach assumes that noise between each receive antenna is uncorrelated.

4. The method of claim 1 wherein the sliding window based approach assumes that noise between multiples of the chip rate do not have a temporal correlation.

5. The method of claim 1 wherein the sliding window based approach assumes no correlation of noise between any of the combinations of the multiple of the chip rate and receive antenna exists.