Performance Analysis of Asynchronous DS-CDMA System with Turbo Code for Short Frame in Multipath Rayleigh Fading Channel

摘要

The performance analysis of asynchronous DS-CDMA system with turbo code in multipath Rayleigh fading channel is investigated. A single cell scenario is adopted where there is perfect channel side information. The performance of turbo code is investigated by simulation in the low signal-to-noise ratio region for different values of processing gain, the number of users, and interleaver length acceptable to voice service. From the results, when the number of iterations of turbo decoding is about 5, there is no longer performance improvement. If E_b/N_o is about 5 dB, even though the length of interleaver is short to be 200, we can know that voice communication is available. Moreover, if the turbo code is adopted to DS-CDMA systems, the effect by the change of processing gain is not large.