一种基于并行FFT的pn码快速捕获算法实现

Algorithm for Rapid Acquisition of PN Code Based on Parallel FFT

扩展频谱通信系统是将基带信号的频谱扩展到很宽的频带上,然后再进行传输的一种系统。pn码的快速捕获,是直扩系统的一项关键的基带技术,文中采用基于最大似然估计的并行FFT算法,完成多路输入信号的频谱分析、载波多普勒频率检测和伪码同步位置的搜索,最后给出了Matlab仿真及RTL实现电路图。该算法已在工程中得到应用,对提高多路扩频信号,同时接收系统捕获时间有良好的效果。

Spread spectrum communication is a system of expanding the baseband signal spectrum to wide band and transmitting.Rapid acquisition of pn code is a key baseband technology of Straight extender system.This paper achieves the spectrum analysis on multiple input signals,doppler frequency detection of carrier and pn code synchronous position search by adopting a parallel FFT algorithm based on the maximum likelihood estimation,and finally gives Matlab simulation and RTL circuit diagrams.This algorithm has been put into practical use in engineering and shows good effect in improving multi-channel spread spectrum signal and receiving system capture time.