Performance evaluation of DS-CDMA system with M-ary orthogonal signaling

The effects of signature sequence on the performance of direct-sequence code-division multiple-access (DS-CDMA) systems employing Walsh M-ary orthogonal signaling are considered. The mean-squared value of multiple access interference (MAI) is derived by treating the signature sequence as deterministic. The numerical results show that Walsh orthogonal signaling changes the original properties of signature sequences, and a different choice of signature sequence results in significant performance difference. These results can be used as guides in selecting signature sequences for systems that employ Walsh M-ary orthogonal signaling.