无系统误差的CPⅢ精密三角高程控制网仿真研究

Simulation study of CPⅢ precision triangular elevation control network under no system error

利用精密三角高程测量代替精密水准建立CPⅢ高程控制网将大大提高CPⅢ控制网建网的速度。然而由于大气折光、地球曲率以及垂线偏差等系统性误差的影响,CPⅢ精密三角高程控制网的精度通常难以完全满足规范的要求。文中通过仿真数据对无系统误差CPⅢ精密三角高程控制网进行了研究,得出如下结论:CPⅢ精密三角高程控制网在仅受到偶然误差的影响下,其相邻点间高差中误差可以达到0.15 mm以下;采用增加测回数、提高基准点密度以及限制控制网长度等手段对于提高控制网精度影响甚微。因此,进一步提高CPⅢ精密三角高程控制网的精度,需要从解决系统误差着手。

The precise trigonometric elevation measurement used instead of precise leveling to establish CPIII elevation control network will greatly improve the speed of CPIII control network construction.However,due to the influence of systematic errors such as atmospheric refraction,earth curvature and vertical deviation,the accuracy of CPIII precision trigonometric elevation control network is usually difficult to fully meet the requirements of specifications.This paper studies the precision triangular elevation control network without systematic errors through simulation data,and draws the following conclusions:under the influence of only accidental errors,the error of the precision triangular elevation control network can reach less than 0.15mm between adjacent points;adopting increasing the number of return measurements,increasing the density of reference points and restricting the length of control network and other means have little effect on improving the accuracy of control network.Therefore,to further improve the accuracy of CPIII precision trigonometric elevation control network,it is necessary to start with system error.