【作者】 张学芬；

【导师】 李斌；

【作者基本信息】 长安大学 ， 大地测量学与测量工程， 2007， 硕士

【摘要】 全球定位系统(Global Positioning System—GPS)是美国军方20世纪90年代建成部署的全球卫星导航定位系统,具有观测点间无需通视、定位精度高、观测时间短、提供三维坐标、操作简便以及全天候作业等优点,已广泛应用于工程建设的各领域,并逐步取代了一些传统的测量方法。作为一种实时高效、覆盖全球的卫星定位技术,GPS平面与高程定位的精度不够平衡。在大范围区域内,其平面定位精度是常规测量技术难以比拟的,而在高程定位上,GPS只能提供给我们高精度的大地高,而非工程应用中所使用的正常高。这使得GPS技术在工程应用上,特别是与高程有关应用上遇到现实挑战。为了提高GPS高程定位精度并使之满足工程应用要求,就需要进一步研究GPS大地高与正常高之间的转换关系,即研究高程异常问题以及GPS高程合适、简便、有效的工程应用实现途径和手段。本文在学习、把握GPS发展与GPS大地高、正常高和正高概念及其关系基础上,综述了GPS高程拟合的原理和常用方法;基于MATLAB平台,重点利用数值逼近法中比较典型的几种拟合方法(多项式拟合法、多面函数拟合法、加权平均拟合法以及移动曲面拟合法),对某测区实测数据进行了拟合计算;在对拟合模型及其计算结果的综合比较和分析的基础上,评价了拟合模型的精度,并给出了具体的结论和建议。针对GPS高程转换时可能存在数据粗差及所选用拟合模型的参数问题,论文还对模型进行了抗差估计和参数优选,并通过实例验证了抗差估计和模型参数优选方法的适用性和有效性。最后,为了工程应用的现实需要,论文还尝试了基于MATLAB环境的GPS水准拟合功能集成及其应用界面开发,实现并提供了基于专业计算软件的可靠而便捷的GPS水准拟合问题整体解决方案。更多还原

【Abstract】 Global Positioning System(GPS)is the global satellite navigation and positioning system which the American Military completed in the 1990s.With the advantages such as don’t need intervisibility between the observation point, high positioning accuracy, short observation time, provides three-dimensional coordinates, simple operation and all-weather work, it has been widely used in construction fields, and gradually replace some of the traditional surveying technique.As one kind real-time highly effective and covers global satellite positioning technology, the positioning accuracy of GPS in plane and elevation is not balanced. The accuracy of conventional technology can not match to the plane positioning of GPS, but in the elevation positioning aspect, GPS only can provide for us the high accuracy geodetic height, but not the normal height of the engineering application. This makes the GPS technology to face the reality challenge in the elevation application. In order to improve the GPS elevation pointing accuracy, and make it meet the application requirements, it is necessary to further study the transformation relations between the GPS geodetic height and the normal height, namely research abnormal height question, and regarding how to look for the appropriate, simple and effective ways and means about engineering application of GPS height.This article discusses the GPS development as well as the concept of the GPS geodetic height, normal height and orthometric height and three mutual relations. Then it summarized the GPS height fitting principle and some commonly used methods. Focusing on using some typical fitting methods of the numerical approximation method, such as multinomial surface fitting, Hardy function interpolation, weighting method, moving surface model, to deal with the survey data of one area, witch are based on MATLAB platform. By comparing and analyzing the fitting results, we give different fitting model accuracy evaluation and some concrete conclusion and suggestion.In view of GPS height transformation maybe exist gross errors in the known survey data and unnecessary fitting model parameters, the paper has also carried on robust estimation and optimizing parameters, and has confirmed the applicability and effectiveness of them.Finally, the paper has carried on the GPS level fitting function integration and the application interface development based on the MATLAB environment to the practical needs of the engineering application. It provides the realistic way and the technical means to solve the GPS leveling fitting problem by MATLAB software effectively, reliably and conveniently.更多还原