A two-stage decorrelating detector for DS/CDMA systems

This paper presents an improved two-stage decorrelating detection scheme fo r direct-sequence code-division multiple-access (DS-CDMA) systems. Decorrel ator outputs corresponding to each user are tested to determine whether or not a final decision can be made with high reliability. For users with high reliability, a hard decision is made at this stage. For the remaining user s, a conditional quantization algorithm is employed before a decision is ma de, Results indicate that significant performance enhancement can be achiev ed at the expense of a modest increase in computational complexity. The alg orithm is also applied to synchronous as well as asynchronous multipath cha nnels with excellent results. We also extend the two-stage decorrelating de tection scheme to time-variant communication scenarios and present:ln adapt ive version of the two-stage decorrelator.