BER performance analysis using co-channel interference Bernoulli model in a dual-chip rate DS/CDMA system with parallel correlator

A DS/CDMA system may use multiple chip rate to support multi-data rate services and provide extra divisions among users. The technique is called "code and chip rate division multiple access (C/sup 2/RDMA)" and its BER performance for a two-chip rate system is analyzed. Two methods (using co-channel interference Bernoulli model and Gaussian approximation) are compared. The results show that C/sup 2/RDMA performs well for both small and large sized systems, particularly when a parallel correlator is employed for the lower chip-rate receivers. Various spreading code families such as M-sequence, Gold/Gold-like code, Kasami code and Walsh code are compared as well.