Research On The Three-dimensional Geodetic Datum And The Quasi Geoid Of Shenyang

It has been the geodesy research hotspot to determine the centimeter-dimension local quasigeoid currently. With development of the GNSS technology, it has been a trend to solve the centimeter-dimension orthometric height or normal height directly via the geodetic height got through GPS positioning.Quasigeoid refinement is an important part of the geodetic survey research, the geophysics research and other disciplinary researches, as well as an important basic surveying & mapping project.In this paper, based on the deep research of the three-dimensional geodetic datum establishment and the quasi geoid-related theories, the high-precision three-dimensional geodetic datum of Shenyang has been studied with the GPS technology, the second-class leveling conjunction technology and the modern earth gravitational field determination theories & methods, and matching of the GPS leveling quasi geoid & the gravity quasi geoid has been carried out with the method of spherical cap harmonic analysis. Moreover, through experiments, precision of spatial & geographic data foundation framework of Shenyang has been analyzed and verified to make the following conclusions:the average precision in the horizontal direction of Shenyang's Class C GPS network is 0.0079m and the average precision in the geodetic height direction is 0.012m; the resolution of quasi geoid is 2'30"X 2'30" and the precision is 0.01m, which meets the requirements for general surveying & mapping engineering, so the basic three-dimensional geodetic coordinate framework of Shenyang consistent with the national spatial data foundation framework is established to provide the vast surveying & mapping service for various urban economic construction activities.Establishment of Shenyang's high-precision three-dimensional geodetic datum and determination of the quasi geoid is a hi-tech frontier subject of important values. By studying and implementing the subject, the traditional height measurement operation mode has been improved greatly and application of new surveying & mapping technologies in Shenyang has been accelerated.