一种新的基于FFT的高动态扩频信号捕获方法  

New Acquisition Method of High Dynamic Spread Spectrum Signals Based on FFT

作　　者：黄健[1,2] 张德海[1] 孟进[1,2] 闫大帅 

机构地区：[1]中国科学院空间科学与应用研究中心,北京100190 [2]中国科学院大学,北京100190

出　　处：《电视技术》2015年第9期113-116,139,共5页Video Engineering

摘　　要：由于传统的伪码捕获方法对高动态大多普勒信号捕获困难,提出了一种基于FFT的并行搜索多普勒频偏和伪码相位的快速捕获方法。该方法考虑了高动态下多普勒频率的变化率,先通过延时自相关捕获并补偿多普勒频偏及其变化率,再使用FFT伪码循环相关捕获码相位,最后用MATLAB进行了仿真,验证了该方法的正确性和有效性,该方法适用于大多普勒频偏范围和快速捕获要求。Traditional PN code acquisition algorithm is effectless for high dynamic Doppler shift signals. A new fast acquisition method which parallel searches frequency offset and pseudo-code phase based on FFT. It considers Doppler frequency change rate in high dynamie environment and estimates Doppler frequency shift as well as ehange rate by the delay self-con＇elation combined with FFT and gains code phase estimation by circular correlation. The simulation by using MATLAB verifies that the algorithm is correct and effective. The method is usable tot large range of Doppler shift and short code acquisition time.

关 键 词：高动态 多普勒频偏 伪码捕获 

分 类 号：TN914.4[电子电信—通信与信息系统]