Joint Detection and PN Timing Recovery for DS/CDMA Systems with Smart Antenna

Smart antennas used in code division multiple access (CDMA) multiuser communications can enhance range, reliability and capacity. In this paper, we use least mean square (LMS) algorithm and propose two adaptive antenna receiver structures for direct sequence code division multiple access (DS/CDMA) multiuser systems. The receivers estimate the desired signal and code delay to perform code synchronization by LMS algorithm simultaneously. In the proposed schemes, an "error signal" is used to update the weights of the adaptive beamformer and the estimated code delay. Simulations confirm the good performance, including timing tracking and BER, of the proposed receiver structures.