Yunnan Province Regional Quasi Geoid Refining Method And Accurate Analysis

As the development of the Earth's gravity field model, the surface gravity data, GPS/leveling data, digital terrain model (DTM) and satellite altimetry data and satellite gravity data, Earth's gravity field and other relevant information, they provide the necessary conditions to determine centimeter-level quasi-geoid. Based on centimeter level geoid accuracy requirements, this essay will discuss the problems in China's use of diverse observational data refinement quasi-geoid and give some actual solutions.Research for the quasi-geoid refinement in China, China quasi-geoid CQG2000has been established, and our province (Yunnan) due to the complex topography, at present in this area is not mature. This paper has discussed the geometric GPS/leveling method, the gravity method and the geometry and gravity combination method. Firstly, it explores several fitting and interpolation models and regional GPS/leveling fitting height anomaly and Case Analysis, and summer up the GPS/leveling to establish the suitability of the quasi-geoid model range and terrain types. Secondly, it also introduces the GPS leveling and gravity data, as well as Earth's gravity field model portfolio to calculate the quasi-geoid. it introduced the latest theories and algorithms of the current international and local gravity field approximation, based on the " Remove-Restore"technology, integrated application of terrestrial gravity observation data, digital terrain model, the gravity field model, especially GPS/leveling data. Furthermore, this paper introduces the thinking and method of provincial quasi-geoid model established in Yunnan Province, And the applications of corresponding development software. and testes the accuracy of the model in combination with various regions'tests data of Yunnan Province, and it also summarizes the stability and practicality of the model. Lastly, it emphasizes under the premise do not have enough gravity data, using of regional GPS/leveling height anomaly control network and provincial refinedquasi-geoid superimposed fusion, It is using local high precision high resolution correct wide-area low precision low resolution, set up local area centimeter accuracy level quasi geoid model; Superposition fusion is key to the residual model analysis. and this paper explores the theory of the polynomial surface fitting and triangulation bilinear interpolation and the weighted average estimation method. Finally using different methods from the test data to draw precision statistics and contrast. Sums up the use of triangulations bilinear interpolation and weighted average method to estimate refinements quasi-geoid get elevation can instead of trigonometric elevation and fourth leveling. And prospects, based on this quasi-geoid model used continuous operation benchmark stand synchronous rapid static model or observation network RTK mode. Realize obtain real-timely the normal high elevation of meet engineering measurement precision...