Blind adaptation algorithms for direct-sequence spread-spectrum CDMA single-user detection

Single-user detection techniques mitigate multiple access interference and the near-far problem in direct-sequence spread-spectrum CDMA systems. Trained adaptation algorithms are commonly used to adapt the receivers. Two blind adaptation algorithms, the Griffths' (1989) algorithm and the linearly constrained constant modulus algorithm (LCCMA), are proposed for this application. Simulation results show a performance greatly superior to that of the conventional receiver and close to the case of trained adaptive receivers. Blind adaptation allows for a much more flexible network design by eliminating the need for a training sequence.