An FFT-Based DS-SS Signal Acquisition Algorithm Research

Demands on acquisition capability of spectrum signal receiver in direct spread spectrum system (DS-SS) is increasing. This paper presents an acquisition strategy of PN (pseudo noise) code for spectrum signal receiver in highly dynamic and low signal-noise ratio (SNR). An algorithm based on radix-2 FFT is applied. Four re-sampling methods i.e. zero-padding, near-fetching interpolation, linear-interpolation and sinc-interpolation are studied. In order to acquire the PN code under low SNR environment, we developed an algorithm of PN code correlation power integrated on multiple periods and give concrete illustrations aimed at the required system, which is testified to be effective for weak signal acquisition in DS-SS application.