复杂环境下GPS接收机基带信号处理研究及实现-信号与信息处理专业论文.docxVIP

摘 摘 要 I万方数据 I 万方数据 摘 要 卫星导航系统不仅在民用领域发挥着巨大的经济效益，而且在军事领域也有着重 要的作用。基于此原因，我国正在建设北斗全球卫星导航系统。高动态、高灵敏度技 术对于接收机能否在复杂环境下应用起着至关重要的作用。因此高动态、高灵敏度接 收机技术的研究对我国卫星导航系统的建设和发展具有重要的现实意义。 本文以实现高动态、高灵敏度硬件接收机为最终目的，重点研究卫星导航接收机 的高动态、高灵敏度关键技术。主要包括捕获、跟踪两部分，首先详细介绍了复杂环 境下捕获技术的硬件实现方案，并给出了捕获时间、捕获门限、捕获灵敏度、多普勒 步进、积分策略等关键参数指标的设计，给出了硬件实现的总体框架和相应的仿真以 及实测信号结果。然后，论文进行了跟踪环路的设计，包括总体方案设计，复杂环境 下的锁频/相环、环路带宽、积分策略、码/载波环路等关键参数指标的设计，通过软 硬件环境实现仿真及实测信号结果。接着实现了一种适合硬件接收机的载噪比估计算 法，根据位同步的特点，采用了直方图估计法和最大似然估计算法以适应不同的复杂 环境，并完成了硬件实现。 最后介绍了基于 FPGA+DSP 的 GPS 接收机硬件平台，设计实现了硬件接收机， 对接收机关键参数指标进行测试，通过硬件实测结果论证了本文所述方法和电路设计 的灵活性、正确性和可行性。 关键字：捕获跟踪；高动态；高灵敏度；GPS 硬件接收机 Abstract Abstract II万方数据 II 万方数据 Abstract The Satellite Navigation System does not only bring huge economic benefits to the civilian area, but also plays an important role in the military field. For this reason, Beidou Global Satellite Navigation System is being built in China. High-dynamic and high-sensitivity technology plays a crucial role for the receiver to work in complicated environment. Therefore, the research of the high-dynamic and high-sensitivity receiver has a practical significance for establishment and development of the Satellite Navigation System in China. In order to develop the high-dynamic and high-sensitivity hardware receiver, this thesis focuses on the key technology of the receiver with high-dynamics and high-sensitivity. It consists of acquisition and tracking. Firstly, this paper details the program of the hardware implementation about acquisition technology in complex environment. It proposes the key parameter index design of the acquisition time, the threshold of acquisition, the sensitivity of acquisition, the doppler stepper, integral strategy and the overall framework, corresponding simulation and measured signal results of the hardware implementation. Secondly, the carrier and code loop are introduced in detail, which include the design of scheme, FLL/PLL discriminator design, the bandwidth analysis, DLL design and control in complex env