Probability of acquisition with noncoherent and differentially coherent code acquisition in Doppler
J. Iinatti, Ari Pouttu · 2002
This paper considers the use of differentially coherent (DC) matched filter (MF) code acquisition in a direct-sequence (DS) spread-spectrum system. An approximate analysis in an AWGN channel and in a Doppler environment is presented. The performance measure is the probability of acquisition, P/sub acq/, during a certain observation interval. The performance is compared to conventional noncoherent (NC) code acquisition. The differentially coherent method requires about 2.5 dB lower signal-to-noise ratio when optimal thresholds are used and no Doppler shift exists. The DC method has a better performance if the normalized Doppler shift is of the order of 0.15 or less.