A Fast PN Code Acquisition Algorithm with the Constraints of Low Input Signal Noise Ratio and Low Constant False Alarm Probability
AN Jian-ping, Yebing Shen, Aihua Wang, Luo Changqing · Acta Armamentarii · 2007
Pseudo noise(PN) code acquisition with very low false alarm and miss probability in a limited period of time is required for the short frame burst-mode directsequence spread-spectrum(DSSS) communication systems.A novel noncoherent approach,based on multi-symbol accumulation-to-PN code acquisition and digital matched filters(DMFs),was proposed to solve the problem.It is an improved mode of the traditional DMF single dwell algorithm.By using the method of multi-symbol accumulation,the proposed algorithm can increase the signal-noise ratio(SNR) of code phase detection statistics,so the mean acquisition time is greatly shortened under the constraints of low input SNR and low false alarm probability.Its performance in QPSK-DSSS systems was analyzed.The simulation results show that the proposed algorithm is able to capture PN code fast under the constraints of low SNR and low false alarm probability.