PN码捕获中部分相关器长度的确定

在大多普勒频移环境下,使用一组部分相关器结合快速傅里叶变换进行伪码捕获,可以将码相位-多普勒频率的二维搜索降为一维搜索,大大减少了捕获时间。基于部分匹配滤波器（PMF,Partial Matched Filter）-快速傅里叶变换（FFT,Fast Fourier Transform）的PN码捕获中,部分相关器的相关运算会使滤波器的频幅响应产生衰减。这里推导了相关损失与相关器长度和多普勒频移的关系,为分析捕获系统的捕获范围和选取相关器长度提供理论依据,同时给出选取分段相关器长度X值的方法。仿真表明给出的选取X值的方法是可行的。

Selection of PMF Size in PN Code Acquisition

A set of Partial Matched Filters in combination with Fast Fourier Transform are employed to acquire pseudo code in Doppler frequency shift environment,and this could reduce the two-dimensional search of code phase and frequency to one-dimensional search,and thus significantly lessen the acquisition time with large Doppler frequency shift.In the PMF-FFT based PN code acquisition,correlation calculation of partial matched filter(PMF) would make frequency-response decline.The connections between coherent combi...