Trellis coded spread-spectrum for fading channels

A direct-sequence spread-spectrum (DS/SS) communication system that uses a form of trellis coding is considered. In this system, the trellis code is used to select the signature sequence which is transmitted. This system is analyzed for a channel model which includes the effects of multiple-access interference, Gaussian noise, and Rician fading. Analytic performance results are reported for several systems in the form of bit error rate (BER). These results are shown to compare favorably with uncoded systems over a aide range of fading channels. The tradeoff is a modest increase in system complexity. The trellis coded system is shown to offer performance improvements over the uncoded system for a wide range of channels. The techniques presented can be adapted to the case of random signature sequences, but the results for a deterministic signal constellation are presented