Smart Antennas for Multiuser DS/CDMA Communications in Multipath Fading Channels - Spread Spectrum Techniques and Applications, 2004 IEEE Eighth International Symposium on

Smart antennas, with spatial processing, used in code division multiple access (CDMA) multiuser communications can enhance range, reliability and capacity. Moreover, the adaptive beamforming technologies can remove unwanted noise and jamming from the received signal. In this paper, we use least mean square algorithm and propose four adaptive antenna receiver structures for directsequence (DS) CDMA multiuser environment with multipath fading channels. Narrowband and wideband adaptive array receiver structures are considered in this paper. LMS algorithms are employed in both narrowband and wideband receiver structures to adjust the spreading code coe cients. We call these new schemes as Wiener code filters. The weights of the adaptive beamformer and the spreading code are updated every bit interval, so the computational complexity is very low. Simulation examples are given to compare the performances of the proposed receiver structures.