A simplified equalization method for asynchronous cooperative relay systems

In this paper, asynchronous cooperative relay systems based on distributed linear convolutional space-time codes are investigated. By utilizing the banded Toeplitz property of the equivalent channel matrix, a block minimum mean square error (MMSE) equalization method employing the Trench algorithm to solve the Toeplitz linear equations is proposed, which avoids the high order matrix inversion operation in the traditional MMSE equalization method. The computation of the equalization operation is further simplified greatly by converting the high order banded Toeplitz linear equations to the low order ones. Simulation results show that satisfactory system performance can be achieved by employing non-minimum-order non-trace-orthogonal generator polynomials.