Parallel acquisition of PN sequences in Rayleigh fading channel andthe application to the multi-carrier CDMA systems

摘要

We propose an improved scheme for parallel acquisition of PNsequences of multi-carrier direct-sequence spread spectrum systems inthe Rayleigh fading channel. Unlike conventional parallel acquisitionschemes, the search region of each searcher in the proposed scheme ismodified so that it is overlapped with that of other searchers. The useof the proposed search scheme enables us to obtain multiple informationon the same code phase at different time instants, providing the timediversity effect. This effect results in acquisition performance robustto fading. The performance of the proposed acquisition scheme isanalytically evaluated in terms of the detection probability and themean acquisition time in the Rayleigh fading channel. Numerical resultsshow that the proposed scheme can provide acquisition performance robustto channel conditions, including fading and correlation between thesubchannels