A CONSTANT MODULUS ALGORITHM FOR MULTIUSER SIGNAL SEPARATION IN PRESENCE OF DELAY SPREAD USING ANTENNA-ARRAYS

We consider the problem of recovering p synchronous communication sign als that are transmitted through a multiple-input/multiple-output (MIM O) linear channel and are, therefore, received in the presence of both interuser (IUI) and intersymbol interference (ISI), A multichannel li near equalization approach is taken, and we propose to adjust the equa lizer coefficients with a blind adaptive algorithm (without the use of training data), This multiuser constant modulus algorithm (MU-CMA) is derived from the minimization of a cost function that penalizes devia tions of the equalized signals from the constant modulus property as w ell as cross-correlations between them, The proposed scheme appears to be an appealing technique for multiuser blind equalization that combi nes good convergence properties with low computational complexity.