Skip to Main Content
The bit-error-rate (BER) performance for a direct-sequence code-division multiple access (DS-CDMA) system with complex signature sequences is investigated in fading channels. Due to the availability of potentially large sets of complex sequences with good correlation characteristics, the interest of using complex spreading sequences in a CDMA system has increased dramatically. The average BER for asynchronous DS-CDMA with general complex signature sequences is derived based on the Gaussian approximation method. We investigate the recently introduced orthogonal unified complex Hadamard transform (UCHT) sequences. Numerical examples show that BER performance of UCHT sequences is better than that of Gold sequences for the system under consideration.