A New Analysis of Direct-Sequence Pseudonoise Code Acquisition on Rayleigh Fading Channels

Abstract—Accurate performance evaluation of direct-sequence pseudonoise code acquisition on Rayleigh fading channels is investigated in this paper. For fading channels the homogeneous Markov chain model, used to characterize the acquisition process over additive white Gaussian noise channels, is no longer valid due to the correlations between cell detections incurred by fading. Hence, the traditional direct and flow-graph approaches for performance evaluation of the code acquisition are not applicable to fading channels. In this paper, a new analysis is proposed for accurate evaluation of the acquisition performance on Rayleigh fading channels. The analysis is quite general and can include various search strategies, types of correlators, and test methods with different performance measures: probability mass function and/or moments of acquisition time. Analytical and simulation results show that the new method predicts the acquisition perfor-mance very accurately. Index Terms—Direct sequence spread spectrum, pseudonoise code acquisition, Rayleigh fading. I