GPS软件接收机系统设计及仿真实验研究

Study on system design and simulation of GPS software receiver

软件接收机通道模块设计体现着软件算法的核心,接收机运行控制设计决定着整个软件系统的循环。在接收机通道状态分析的基础上设计实现了GPS单频软件接收机,并对自行开发的C/A码信号仿真器产生的数字中频信号进行了实验,分析了捕获和跟踪状态中通道重要参数的时间序列关系,验证了时域串行搜索捕获策略、超前—滞后非相干码跟踪环路以及直方图位同步算法的正确性和通道模块结构设计的合理性。

The design of software receiver channel module embodies the kernel of the software algorithm, and the design of the performance control determines the overall cycle in the system. Based on the analysis of the states of the channel, a GPS signal-frequency software receiver is realized. A test on the software receiver is made with the digital IF signal produced by a C/A signal simulator developed by authors. The time sequence information of the important parameters in the acquisition and track states is analyzed. The analysis result indicates the exactness of the algorithms, which includes the method of serial searching in time domain, the method of tracking with early-late non coherent code tracking loo Pand the bit synchronization way with histogram, and the rationality of the channel module design.