A reduced state Viterbi algorithm for multiuser detection in DS/CDMA systems

Code division multiple access (CDMA) has attracted considerable attention in digital cellular mobile and personal communications. We propose a novel multiuser detector based on the reduced state Viterbi algorithm. It partitions the total K users into G groups according to their power strengths and interference levels, which reduces the computational complexity per binary decision from O(2^K-1) to O(G*2^KG-1/) for asynchronous DS/CDMA systems in AWGN. Theoretical analyses and simulation results are presented to demonstrate the significant performance improvement over the successive interference canceler (SIC)