直序扩频通信中同步捕获的改进算法

An improved acquisition of DSSS system

提出一种用于直序扩频通信的同步捕获改进算法,其核心思想是让输入信号同时通过基本通带和辅助通带两个支路滤波器,经推导得出相应最优的中心频率和带宽.然后分别对两个支路的输出信号进行谱分析,通过比较两个支路输出信号的功率来判决本地PN码是否与输入信号的PN码同步,实现PN码同步捕获.仿真结果表明,该算法捕获性能良好、易于实现,适用于实际的扩频通信系统.

A new synchronization acquisition algorithm of DSSS system is studied in this paper.The key point of the proposed method is letting the received signals pass two branch filters simultaneously.And the output power difference is used for detecting the PN code synchronization moment.The optimal positions of the two filters are deduced by discussing the center frequencies and the pass-bands.Simulation results show that the improved algorithm has high performance,and it is easier to be implemented in a practical spread spectrum system.