Fractionally-spaced array processing for fast fading cellular TDMA signals using cyclic higher-order cumulants

A new approach to cochannel interference rejection in frequency selective fading using an antenna array is presented. The fundamental idea is to exploit the higher-order cyclostationarity of the digitally modulated signals received at the antenna array. The problem of minimizing the noise-free time averaged mean squared error is shown to be equivalent to the problem of minimizing a cost function involving space-time contractions of fourth-order cyclic cumulants. The method is effective in fast fading environments such as those specified in IS-136, the US digital TDMA cellular standard. Results of computer simulations and hardware experiments are presented.