高动态下直扩接收机关键模块的设计与仿真  

Design and simulation of key module of DS-SS receiver in high dynamic

作　　者：王顶[1] 李军中[1] 徐林搏[1] 

机构地区：[1]西北工业大学电子信息学院,西安710129

出　　处：《计算机应用研究》2012年第3期991-993,1001,共4页Application Research of Computers

基　　金：航天支撑技术基金资助项目(2009XW080002)

摘　　要：高动态给扩频信号带来较高的多普勒频移,使伪随机码产生较大的动态时延,很容易造成载波跟踪环和码跟踪环的失锁。为了提高跟踪环路的动态应力,防止跟踪环路失锁,在分析了捕获与跟踪原理的基础上,提出了一种捕获与跟踪的设计方案。该方案捕获采用基于FFT的并行快速捕获算法,载波环采用2阶锁频环FLL(frequency locked loop)辅助3阶锁相环PLL(phase locked loop),码环采用2阶延迟锁定环DLL(delay lockedloop)。MATLAB仿真结果表明,在高达65 g的视距动态应力条件下该设计也能够表现出其精确、稳定的性能。High dynamic creats high Doppler shift to spread-spectrum signal and makes Pseudo-random code have a greater dynamic delay,which is likely to cause carrier tracking loop and code tracking loop out of lock.In order to improve the dyn-amic stress of the tracking loop and prevent tracking loop out of lock,this paper presented a design of the acquisition and tracking based on the analysis of the principle of the acquisition and tracking.MATLAB simulation results show the correctness of this design,and even if in a high dynamic conditions,this design can also have a precise and stable performance.

关 键 词：捕获 跟踪 高动态 多普勒 鉴相器 

分 类 号：TP393.04[自动化与计算机技术—计算机应用技术]