采用省级网络RTK控制测量开展区域高程拟合研究

GPS height fitting research based on provincial network RTK

网络RTK具有高精度实时定位等优势,采用拟合技术可得到满足一定精度的正常高,使其可直接为测绘生产服务。本文通过对一级网络RTK实测数据进行严格剔除处理,得到每测点的最优值,将其与测点的三等水准测量或四等高程测量数据作为输入数据,采用二次曲面高程拟合方法求取某地区高程拟合参数。实验表明,拟合残差最大为4.4cm,模型外符合高程中误差为2.68cm,精度高于"四等"GPS高程控制测量等级要求,按规定只能用于"碎部"等级,但这对缺乏大地水准面精化成果的市区建立控制网具有参考意义。

This paper has obtained the optimal value of each GPS point according to strictly rejecting the measured data of the first order network RTK. Then,the elevation fitting parameters are obtained by the quadric surface fitting model with GPS and leveling data. Experimental results show that the maximum fitting residual is 4. 4 cm and the standard error of the elevation anomaly model is 2. 68 cm,bigger than the requirements of the fourth order GPS height network. According to the regulations,it can only be used in the detail surveying,but it is of reference to the establishment of control network for the urban area which lacks the refined results of the geoid.