一种基于DEM的CGCS2000城市平面坐标系统确定方法

Method for Defining the DEM CGCS2000 Plane Coordinate System Based on the City

针对CGCS2000城市平面坐标系统定义的主要问题,在分析不同城市地理空间形状基础上,提出不同的解决方法。尤其是城市平面坐标系统确定在解决中央子午线与高程抵偿面确定的最优方案评价中,提出了DEM网格占比法解决CGCS2000城市平面坐标系统定义中的投影变形问题,验证结果优于最小二乘法。

This paper proposed different solutions based on the analysis of different urban geospatial , aiming at the problem of the urban CGCS 2000 plane coordinate system definition .The DEM grid ratio method was proposed to solve problems of projection deformation in urban CGCS 2000 based on the optimal evaluation scheme of cities plane coordinate system definition depend on compensating level surface and central meridian .It is verified that the DEM grid ratio meth-od is better than least square method .A view point was proposed that the accuracy of four-parameter conversion is high-er than the seven-parameter conversion in urban areas with range of no more than 90 km span from east to west .