A modified CM array algorithm for fading channels

A new constant modulus (CM) array algorithm with a time-varying step size is presented. It is designed for use in a multistage system where each stage recovers one cochannel signal. The new algorithm ensures that a stage tracks the same source during fast fading conditions (such as those found in mobile radio communications), thus yielding reliable signal estimation in a nonstationary environment. We present the cost function associated with the algorithm and compare it to that of the original CM array. Computer simulations for Rayleigh fading channels are presented to illustrate the improved tracking behavior of the multistage CM array system.