Performance analysis of DS-SS PN code acquisition systems using soft-decision techniques in a Rayleigh-fading channel

A soft-decision method employing multiple threshold values for PN code acquisition in direct sequence spread spectrum (DS-SS) systems is described. We apply this technique to conventional search algorithms, double dwell serial search and hybrid search, and analyze them in terms of mean code acquisition time. For the analysis, we present mathematical models of proposed algorithms under a Rayleigh-fading channel. Numerical results show that our proposed schemes outperform conventional ones because multiple threshold values mitigate the possible decline in search performance caused by the use of a single threshold in conventional algorithms.