A Approach to DS-SS Signal Acquisition Using Larger Step and Serial Acquisition Algorithm

A new acquisition scheme, named larger step and serial acquisition, of PN (pseudo-noise binary sequence) sequences for DS/BPSK (direct-sequence/ BPSK) navigation receiver is introduced with focus on the acquisition problem of long sequences buried deeply in noise. This method is similar with the hybrid acquisition, but especially used in the navigation area. The hardware implementation of the scheme is provided, and the mathematics mode of the acquisition system is presented. Based on the state transferring function of the acquisition system, the mathematic expression of average acquisition time, detection, and false alarm probabilities for the DS-BPSK system in AWGN (additive white Gaussian noise) is derived. The acquisition performance of the system introduced is analysed and simulated with consideration of phase error of PN sequences, Doppler shift and background noise. Overall the results demonstrate that the larger step and serial acquisition presented in the paper is considered both the fast acquisition and less hardware, it is a better method to resolving long sequence fast acquisition in low signal-to-noise condition.