Patent ID: 7164740

Claim:
A wireless communication apparatus comprising: (a) an antenna array; and (b) an orthogonal frequency division multiplexing (OFDM) receiver in communication with the antenna array, the OFDM receiver being configured to perform fast Fourier transforms (FFTs) on signals received by the antenna array so as to separate spatial beams derived from the received signals and process each beam independently, wherein the antenna array comprises N antenna elements and the number of spatial beams is also N, and beam signals “[X]” are transformed to a parallel data stream “[U]” by performing a fast Fourier transform (FFT) beam space operation on the beam signals “[X]” in accordance with the following equation: [U]=[(V 2 {circle around (x)}I 1 )×K×(V 1 {circle around (x)}I 2 )]×[X], where V 2 is an M×M Fourier matrix for M sub-carriers, {circle around (x)} is a Kronecker product, I 1 is an N×N identity matrix, K is a bit reordering matrix which is determined by the size of V 2 , V 1 is an N×N Fourier matrix for the N antenna elements and I 2 is an M×M identity matrix.