节点文献
高动态环境下GPS C/A码信号的捕获与跟踪算法研究
Research on Acquisition and Tracking Algorithm of GPS C/A Signal under High Dynamic Environment
【作者】 倪光华；
【导师】 田红心；
【作者基本信息】 西安电子科技大学 ， 通信与信息系统， 2008， 硕士
【摘要】 本文在深入研究GPS的系统组成、工作原理以及信号格式的基础上,对高动态条件下C/A码GPS接收机设计中遇到的几个关键问题进行了理论分析,并对实现方法进行了研究。主要工作如下:1、对多种GPS信号捕获算法进行了深入研究与分析,针对高动态条件对信号捕获的要求,提出了一种基于PMF算法的C/A码快速捕获方案,并对其性能进行了仿真验证;2、介绍了适应高动态环境特点的几种信号参数估计算法,并选择AFC算法实现跟踪环路。对存在载波辅助的DLL码跟踪环路算法进行了理论研究与性能仿真;提出了一种由叉积自动频率跟踪环(CPAFC)、交叠离散傅立叶变换自动频率控制环(ODAFC)以及科斯塔斯锁相环(Costas)相结合的高动态载波跟踪方案,并利用MATLAB对其性能进行了仿真;3、在完成理论分析的基础上,初步完成了GPS接收机信号跟踪模块核心单元的FPGA设计与功能仿真。
【Abstract】 Based on analysis of the system architecture, principles and signal format of GPS, this thesis makes researches on the problems existing in designing high dynamic GPS receiver, and the corresponding implementation is also discussed. The author’s researches involve three aspects as follows:1. Via thorough theoretical analysis and research about several GPS signal acquisition algorithms, a fast C/A code acquisition algorithm based on PMF is proposed for high dynamic GPS receiver, which is verified by simulation results.2. Referring several algorithm of high dynamic signal parameter estimation, the AFC is chosen as the basic algorithm of tracking loop. Some research work and simulation on the code loop based on DLL are done. A carrier loop composed of a CPAFC,4-point ODAFC and Costas for high dynamic application is designed with simulation via Matlab.3. Based on the theoretical analysis above, the FPGA design and function simulation on several kernel units of signal tracking block of GPS receiver have been achieved.