GPS附合网三维平差的方法和应用.pdfVIP

GPS 附合网三维平差的方法和应用 施一民,王勇红，张虎，范业明 ( 同济大学 测量系, 现代工程测量国家测绘局重点实验室, 上海 200092) 摘要：提出了对城市及工程 GPS 网作附合网平差的意义和方法，与现有软件所采用的方法不同，不 再是仅固定一个点的三维坐标及固定其余固定点的大地经纬度，而是保持全部固定点的三维直角坐标 不变。这样不仅适应于已建有国家、省级 GPS 网以及一些城市 GPS 基准站网的新形势，而且能因加 入高精度的基准点坐标来提高城市工程 GPS 网的精度、并由此统一到新的全国大地基准。在所研制的 软件中采用了消去未知参数及附加基准方程两种等价的算法，据此研制成的新软件已在宁波市基本控 制网数据处理中正式采用，获得了满意的结果。 关键词 GPS 附合网，三维平差，固定点，基准方程 The Algorithm and Application of Three Dimensional Adjustment of GPS Networks with Several Fix Points Shi Yimin, Wang Yonghong，Zhang Hu, Fan Yeming （Dept. of Surveying and Geomatics,Tongji University,Shanghai,200092,China ） Abstract: This paper puts forward the principle and method of 3D adjustment for GPS networks with several fix points. The method is differed from the traditional methods that are used in the current software . The traditional methods can keep only the 3D coordinates of one point and geodetic longitudes and latitudes of other fix points unchanged, whereas the new method presented in this paper can keep the 3D coordinates of all fix points unchanged. It can not only adapt the new situation that our country and some provinces have built GPS networks with high precision and some cities have established several GPS base stations, but also improve the precision of GPS networks, bring GPS networks into the national geodetic system by introducing some GPS points with high precision as fixed points. The software has used in Ningbo control network and the results are adopted. Key Words: GPS network with several fix points，3D adjustment，fix point，datum equation 1引言 以往用常规技术建立起来的地面控制网不能提供具有足够精度的已知点来控制 GPS 网，因此首级 GPS 控制网常按固定一点或再加一个方位角按独立网予以处理。因若按附合 网来平差、转换GPS 网,会因可观的地面网的固有误差而使GPS 高精度的相对网形