Smart maximum-likelihood CDMA multiuser detection

A fast-low-complexity maximum-likelihood multiuser detector for code division multiple access systems is proposed. It utilizes a best-first branch and bound approach and a constrained memory search. The memory constraint makes the proposed detector realizable, but has negligible performance loss in low signal-to-noise ratio (SNR) and virtually no performance loss in medium-to-high SNR. The results show that the proposed algorithm is much less complex, and that it executes faster than existing maximum likelihood detectors. In addition, the proposed method is suitable for parallel implementation.