重庆市都市区高程异常模型的建立及RTK测量坐标转换系统开发

摘要

WGS-84坐标到城市独立坐标系之间的高精度转换是进行RTK测量的关键,而难点是高程转换。常用的高程拟合算法有平面拟合法、二次曲面拟合法等。平面拟合法适合小范围平坦地区,山区则宜采用二次曲面拟合法。考虑重庆山地城市特点,还应考虑地形起伏对高程转换的影响。试验结果表明,在不考虑重力影响的情况下,利用重庆市都市区已有高程控制点数据,采用基于地形改正的二次曲面拟合法所建立的山地城市高程异常模型能够满足城市测量及工程建设的需要。%The high-precision conversion between WGS-84 coordinate system and the Urban Independent Coordinate System,is the key to RTK survey and its difficulty is height transformation.The common elevation fitting algorithms are plane fitting method,conicoid fitting method,etc.The plane fitting method is used in small flat area,and the conicoid fitting method is used in mountain area.There is undulating terrain effect to height transformation because Chongqing is the mountain city.The result shows that without considering gravity effect,the improved conicoid fitting method based on terrain correction could build mountain city elevation abnomality model with using exist elevation control points,and the model could meet the needs of urban survey and construction.