GPS接收机的中频信号处理算法研究  

Research on Signal Processing Algorithms in GPS Receivers

作　　者：蔡凡[1] 尹燕[1] 张秀忠[1] 

机构地区：[1]中国科学院上海天文台

出　　处：《天文学进展》2007年第1期84-95,共12页Progress In Astronomy

基　　金：国家自然科学基金资助项目(10503009)

摘　　要：该文对GPS接收机的中频信号处理算法进行了研究,内容主要涉及信号捕获、载波恢复和伪码跟踪3部分,详细分析了信号捕获过程中所采用的匹配滤波器法、快速傅里叶算法(FFT)、锁频环(FLL)、锁相环(PLL)以及延迟锁定环(DLL)的算法原理,并对环路滤波器作了相应的阐述,给出环路对应的递推公式．The modern standard satellite navigation receivers are commonly based on ASICs for signal processing and fast microprocessors for application calculations. The software satellite navigation receiver is also developed in recent years. The research on software receivers becomes one trend of satellite navigation receiver. For algorithms on signal processing play an important role in satellite navigation receivers, the paper illuminates the signal processing algorithms in detail. The GPS receiver is widely used at present. So the paper places emphasis on signal processing algorithms about GPS receiver. Signal processing algorithms include three aspects .. the algorithm on signal acquisition, the algorithm on carrier tracking and the algorithm on PRN （pseudo random noise） code tracking. In the part of signal acquisition, the method of using FFT to get the result of circular correlation is introduced. The paper carefully researches the method and discusses the derivation process of the method. In the part of carrier tracking, the paper describes the principle of frequency locked loop（FLL） and phase locked loop （PLL） and analyzes the principle of loop filter. The method of transition from s-domain to z-domain is introduced. The computation of noise bandwidth of the loop filter are expatiated and the structures of one-step digital loop filter, two-step digital loop filter and three-step are given. Other parameters of loop filters are also given. In the part of code tracking, delay-early locked loop （DLL） is introduced. Theoretical analysis and experiment results demonstrate the algorithms in the paper. Through the simulation testing, the performance of combination of PLL and FLL can be acknowledged.

关 键 词：天文观测设备和技术 GPS接收机 软件无线电 匹配滤波器法 快速傅里叶算法 锁频环 锁相环 延迟锁定环 

分 类 号：P228.4[天文地球—大地测量学与测量工程] TN965.5[天文地球—测绘科学与技术]