Constant Modulus Algorithm for Cochannel Signal Separation in Non-Gaussian Impulsive Noise Environments

The separation of cochannel signals is of interest in communication community. Some algorithms based on constant modulus (CM) have been previously developed to separate cochannel signals with the assumption of Gaussian channel noise. The mismatches of noise models between the assumed channel noise and the practical noise may occur. These mismatches will inevitably lead the performance of cochannel signals separation to degrade. In this paper the alpha-stable distribution is employed as noise model to simulate impulsive noise occurring in wireless channel. A constant modulus algorithm is proposed to separate the cochannel signals based on fractional lower-order statistics (FLOS). The convergence of the CM array is analyzed. Numerical simulations are presented to verify the accuracy of the analytical results.