Interference reduction applied to channel estimation in CDMA systems

A multiuser base station receiver for CDMA mobile radio systems is proposed. It is based on a bank of conventional single-user DS-CDMA receivers connected to an adaptive linear combiner. The combiner takes into account the multiuser interference present in the CDMA system. It is the key component of the receiver: it allows one to improve the path delay estimation, to efficiently estimate the amplitudes of the propagation paths, and to benefit from interference cancellation. All this can be exploited to reduce bit error rates or increase system capacity. The receiver is suited for a flexible air interface with multiple and variable bit rates. Long random spreading codes for easy code management and handover may be employed