A novel IS-95 CDMA mobile station receiver structure with smart antenna canceller

The capacity of wireless CDMA systems in the forward link is limited by both intra-cell and inter-cell cochannel interferences. In particular, when the mobile station is close to a cell boundary, the desired signal is disturbed by relatively strong interference from neighboring base stations. In this paper, a receiver architecture with smart antenna followed by a RAKE demodulator is suggested at a IS-95 CDMA mobile station for interference suppression and diversity combining. Such a structure can work well only when the channel vector of desired signal is correctly estimated. We use the identifying spreading codes (as in IS-95 for example) to provide and adaptively correct a channel vector estimate, suppress cochannel interference, hence improve the system capacity