Patent ID: 6463099
Filing Date: 2002-10-08
Classification: H04L

Abstract:
A signal equalization method for a multiple-input, multiple-output (MIMO) wireless communication system in which a wireless channel of said communication system being modeled by a finite-impulse-response (FIR) system of order integer M, said communication system is provided with system diversity having a receiver diversity factor of integer N, said equalization method includes the steps of:devising a system convolution matrix A, wherein said matrix A is a generalized Sylvester matrix comprising (L+1) block rows and (M+L+1) block columns of sub-matrices each of which block is a matrix of dimension NÃ—d, wherein the number of rows of A, being the product of N and (L+1), is made to exceed the number of columns of A, being the product of d and (M+L+1), by selecting an appropriate integer L, said matrix A relates a vector of sampled channel output signals o(m) to a vector of corresponding input signal symbol sequences, s(m), transmitted by a plurality (d) of users at the transmitting end of said transmission system by the relationship o(m)=A s(m), wherein o(m) is a vector comprising a selected sampled channel output signal vector (y(m)) and a plurality (L) of sampled channel output signals ([y(mâˆ’1), . . . , y(mâˆ’L)]) which immediately precede said selected sampled channel output signal y(m), each said sampled channel output signal is a NÃ—1 vector due to system diversity; calculating second order statistics of said vector of sampled channel output signals o(m); selecting suitable linear equalizing functions (G) derived from said second order statistics of said sampled channel output signals; and algebraically operating said vector of sampled channel output signals o(m) by said linear equalizing functions, said algebraic operations are selected so that the results of such operation are equivalent to removing inter-symbol interference elements from said matrix A by forcing all block columns of the matrix A to zero except for a specific block column of A.