深空通信中基于FFT的高动态扩频信号的捕获

在深空通信中，航天器的高动态性使扩频信号引入了高Doppler频移，给捕获造成了巨大困难。针对如此之大的Doppler频移，提出了一种新的捕获方案，即基于FFT算法实现对Doppler频移进行一定程度的补偿，将沿码相位一Doppler频率的二维搜索简化为沿码相位的一维搜索；重点分析了深空通信环境中高速长PN码的捕获性能。理论分析和仿真结果表明，该方法大大缩短了捕获时间，是一种性能优良的伪码捕获方法。

Acquisition of High Dynamic SS Signal Based on FFT in Deep Space Communication

In the deep space communications,it has huge difficulty to acquire spread spectrum(SS) signals with high Doppler shifts for a receiver.A new receiver architecture is presented,which estimates the Doppler shift during the PN phase acquisition.This method can search the code phase and estimate the Doppler shifts simultaneously.The acquisition capability of the high speed long PN code in deep space communication systems is emphasized.The simulation and analysis show that the FFT-based method can efficiently accelerate the acquisition process.