【作者】 张骞丹；

【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， 2007， 硕士

【摘要】 全球定位系统(GPS)是新一代精密卫星导航定位系统。GPS具有全球、全天候、连续实时的精密三维导航和定位能力,有着广泛的应用价值和发展潜力,其中观测点定位(静态和动态)一直是GPS的一个重要研究和应用领域。本文在介绍GPS基本原理的基础上,主要研究GPS多普勒频移估算的方法和GPS绝对定位算法。论文研究工作如下:1.在推导卫星运行参数的数学模型和研究卫星可见性算法的基础上,根据多普勒频移的产生原理,建立了多普勒频移估算的数学模型,并对导航卫星运行参数及多普勒频移特性进行了MATLAB仿真及分析;2.在介绍伪距绝对定位原理基础上,研究定位数据处理方法——最小二乘法和卡尔曼滤波法。首先给出了最小二乘法的解算方程,然后在对卡尔曼滤波基本原理和载体动态模型研究的基础上,根据GPS定位原理,建立了GPS定位模型,为了提高滤波器的动态性和跟踪性,论文采用自适应卡尔曼滤波技术将真实的状态从各种随机干扰中最优估计出来,并且仿真和比较了最小二乘法和卡尔曼滤波法解算结果;3.初步完成了GPS接收机导航解算的部分模块的DSP实现。更多还原

【Abstract】 Global Positioning System (GPS) is a precise positioning system of new generation. It has the potentials of application and development due to its advantages of all-global, all-weather and high accuracy. The point positioning (both stationary and dynamic) is highlighted in research and application.Based on the principles of GPS system, the Doppler Frequency-shift Estimation of GPS and absolute positioning algorithms have been studied in this thesis. Main works of this thesis are as follows:1. The Doppler Frequency-shift Estimation of GPS is discussed and the mathematics models of satellite movement parameters are established. Then the algorithm of visibility and the model of doppler frequency-shift estimation are presented. The above models are simulated with MATLAB.2. The principles of pseudo-range measurement absolute positioning are studied. The models of the least square are described, and Kalman filtering algorithms are studied in detail. Based on research on the principle of standard Kalman filter and analysis of dynamic models which describes the motion of the user, general models in GPS positioning are established. In order to improve dynamic and tracking of filter, adaptive Kalman filtering is used to optimally estimate the true position of target from all kinds of random errors. The models of the least square and Kalman filtering are simulated with MATLAB.3. The absolute positioning algorithms have been partially implemented with DSP.更多还原