基于截断非相干累加的长码捕获方法  

A method of long code acquisition based on truncated non-coherent accumulation

作　　者：汪德鑫 杨宇晓[1] 郁丰[1] 张雷[2] WANG Dexin;YANG Yuxiao;YU Feng;ZHANG Lei(Nanjing University of Aeronautics and Astronautics College of Astronautics,Nanjing 210016,China;Xi’an Satellite Control Center,Xi’an 710043,China)

机构地区：[1]南京航空航天大学航天学院,江苏南京210016 [2]西安卫星测控中心,陕西西安710043

出　　处：《现代电子技术》2020年第1期5-8,共4页Modern Electronics Technique

基　　金：国家自然科学基金（61673212）

摘　　要：随着电子对抗的逐渐加剧,卫星信号的扩频体制日益复杂,对接收端的扩频码捕获造成了严峻挑战。提出一种基于截断非相干累加的Y码捕获方法,该方法以W码和P码的特定时序关系为先验知识,通过对Y码信号的截断处理、FFT相关和多段数据的非相干累加,实现低信噪比条件下的Y码信号捕获。仿真结果表明,由于加密W码的干扰,传统捕获方法已无法完成Y码信号的有效捕获,而所提截断非相干累加法仍可实现捕获,具有显著优势。With the gradual intensification of electronic countermeasures,the spread spectrum system of satellite signals is more and more complex,which poses a severe challenge to the acquisition of spread spectrum code at the receiving terminal.In view of the aforementioned phenomenon,a method of Y⁃code acquisition based on truncated non⁃coherent accumulation is proposed,which takes the specific time sequence relationship between W⁃code and P⁃code as the prior knowledge,and realizes the signal acquisition of Y⁃code at low signal⁃to⁃noise ratio by truncation of Y⁃code signal,FFT(fast Fourier ransform)correlativity and non⁃coherent accumulation of multi⁃segment data.The simulation results show that the traditional acquisition method fails to fulfill the effective acquisition of Y⁃code signal due to interference of encrypted W⁃code,however,the method of truncated non⁃coherent accumulation proposed in the paper can still fulfill the acquisition,which has remarkable advantage.

关 键 词：电子对抗 Y码 直接捕获 非相干累加 GPS 低信噪比 

分 类 号：TN927-34[电子电信—通信与信息系统]