A constant modulus blind adaptive receiver for multiuser interference suppression

In this paper we investigate the ability of the Constant Modulus (CM) crite rion to adaptively suppress Multiple Access Interference (MAI) in Code Divi sion Multiple Access (CDMA) channels without the need of training sequences . In the absence of noise, we show that the resulting receiver is able to c ompletely remove the MAI. We also show that, for high SNR values, CM receiv ers perform the same as Minimum Mean Square Error (MMSE) receivers therefor e exhibiting a desirable balance between MAI suppression and noise enhancem ent. The main limitation of CM receivers is that they can be captured by an interferent user. However, we present an initialization strategy that prac tically overcomes this problem. (C) 1998 Published by Elsevier Science B.V. All rights reserved.