| This thesis mainly investigates a novel CDMA system based on orthogonal complete complementary codes (CCC), i.e. CCC-CDMA system. The core of the proposed new CDMA system is the use of orthogonal complete complementary codes, whose autocorrelation function is zero for all even and odd shifts except the zero shift and, whose crosscorrelation function is zero for all possible shifts. The new CDMA system offers MAI-free operation in both up- and downlink transmissions, which can significantly enhance the system capacity. It is particulary suited to multirate signal transmission due to the use of an offset stacked spreading modulation scheme, which simplifies th'e rate-matching algorithm relevant to multimedia services and facilitates asymmetric traffic in up- and downlink transmissions for IP-based applications.First, the thesis introduces the correlation properties of complete complementary codes and compares with other traditional sequences. Then the code generation principle is described, together with the software implementation. Second, the transmission and reception models of basedband CDMA system based on complete complementary codes in up- and downlink are discussed and its performance in AWGN channel is analyzed and evaluated through simulation. Third, a receiver for multipath signal reception is investigated, which consists of two matched filters: one for channel impulse response estimation and the other for data detection. The performance of new CDMA system under simple multipath, rician and rayleigh fading channels is evaluated using simulation. Fourth, synchronization methods of CDMA system are discussed. Acquisition and tracking synchronizations of complete complementary codes are simulated, and carrier and frame synchronizations of system are also implemented. Lastly, various aspects of the proposed system and possible future works are discussed. The thesis also addresses technical limitations of the new CDMA architecture.
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