Patent ID: 8290082
Filing Date: 2012-10-16
Classification: H04B,H04W

Abstract:
1. A method for signal communication in a multi-user radio communication system including a transmit station, having N>1 transmit antennas, and U≧2 receive stations, each receive station having at least one receive antenna and the summed number S of receive antennas of receive stations satisfies 1<S≦N, wherein signals are transmitted-received by means of F≧1 physical channels, the method comprising: estimating transfer coefficients of all possible spatial communication channels respectively; and transmitting signals by the transmit station and receiving signals by receive stations using F physical channels, wherein the step of transmitting signals by the transmit station comprises: forming a channel matrix H of the physical channel using estimates of spatial channel transfer coefficients; forming a real-valued vector a forming a linear multi-user transformation matrix W generating a perturbed real-valued vector of transmitted modulation symbols by adding the real-valued transmitted modulation symbols vector to an optimal perturbing vector; determining the optimal perturbing vector in such a way as to minimize the transmitted signal power; forming a vector of transmitted signals x by multiplying a non-normalized transmitted signals vector x transmitting a set of signals corresponding to the elements of the obtained vector x over an appropriate physical channel via all transmit antennas, wherein the step of receiving signals by receive stations comprises: receiving signals at each of U receive stations in a physical channel of each receive antenna; wherein the reception is carried out in such a way that a signal y is formed as a complex number with a modulo and an argument corresponding to the amplitude and phase of the signal received by this physical channel; normalizing signal y by multiplying it by a normalizing coefficient C obtaining real and imaginary parts of the normalized signal y performing a modulo operation by modulo A for resulting signals z and c; where └x┘ is an integer part of x, comprising the maximum integer less than x, the signals {tilde over (z)} and {tilde over (c)} are used to form a complex signal forming values of a complex signal {tilde over (y)} in each physical channel of each receive antenna are used to demodulate and decode the received signal.