动态环境下基于FFT实现伪码快速捕获

A FFT-based Approach for PN Code Fast Acquisition Operation in Dynamic Situation

无线电导航系统中 ,载体动态性引入的多普勒频移对扩频信号捕获造成了很大困难。针对全数字化实现的扩频接收机 ,提出了一种新的捕获方案 ,即基于FFT算法实现对多普勒进行一定程度的补偿 ,解决了高动态环境下伪码序列的快速捕获问题。理论分析和计算机仿真结果表明 ,该方法简单有效。

It is difficult for a receiver operating in dynamic situation to realize spread spectrum signal acquisition in navigation system. For a receiver that realized by all digital model, a new acquisition mode called FFT based algorithm, is presented, which estimates the Doppler shift during the PN phase acquisition. The algorithm solves the problem of signal acquisition when the receiver operating in dynamic situation. The analysis and simulations show that the FFT based algorithm is simple, efficient and very suitable for DSP implementation.