Study On The Refinement Of Geoid In Complex Areas Of Terrain

With the rapid development of spatial positioning technology, especially the GPS positioning technology and high-precision high-resolution geoid model are gradually established, improving the local three-dimensional and dynamic geospatial framework reference. The establishment of local three-dimensional, dynamic geospatial reference framework and the refinement of regional geoid will be the future direction of the national or local mapping benchmark construction. Most data processers are facing a problem which is the automatical process of the scale GPS data in the establishment of geospatial reference frame. Meanwhile, in the absence of gravity data and terrian data in complex tarrain areas, how to refine geoid is still a research topic for the majority of researchers and engineers. Therefore, the study of automatically processing the large-scale GPS data and the geoid refinement in complex tarrain areas is of high practical and theoretical value. This paper analyzes the features of Python and the advantages of GAMIT/GLOBK software in solving data in the large-scale network of GPS, and develops an automatical processing system of the GPS data with Python programming language on the basis of GAMIT/GLOBK software. Meanwhile, by studying the systematic bias between the regional geoid and WGS-84ellipsoid, the vertical deviation calculated is1.5363m between the geoid of the study area and the WGS-84ellipsoid. The research focuses on methods of the geoid refinement in the absence of gravity data and terrian data in complex tarrain areas, and proposes the combined model between the multi-faceted functions and robust least squares. The gravity geoid is corrected to the geometric geoid under the control of the geometry of the geoid. The final accuracy of geoid is better than5cm. The residual height anomaly field model and geoid model of the study area with the help of Matlab software are established.