海底控制点定位的半参数平差模型法

摘要

This paper focuses on solving the problem of seafloor control point absolute positioning with low vertical accuracy based on the survey ship sailing circle.The method of dealing with the systematic error based on semi-parametric adjustment model was proposed.Firstly, the influence of sound speed change on ranging error is analyzed.Secondly, a semi-parametric adjustment model for determining three-dimensional coordinates of underwater control points was established.And respectively proposed solutions under two different conditions, the observation duration is an integral multiple or non-integer multiple of the long-period term of the ranging error.Simulation experiment results show that this method can obviously improve the accuracy of vertical solution of seafloor control point compared with difference technique and least square method when internal waves exist and observation duration is less than an integer multiple of the long-period term of the ranging error.%针对圆走航确定海底控制点三维绝对坐标存在垂直解精确度差的问题, 本文提出了基于半参数平差模型处理测距系统误差的方法, 首先分析了声速变化对测距误差的影响, 其次在圆走航观测方程的基础上建立了水下控制点三维坐标解算的半参数平差模型, 分别给出了观测时长为测距误差长周期项整数倍与非整数倍时的解算方法.仿真试验表明, 当内波存在且观测时长不足测距误差长周期项的整数倍时, 该方法相比于差分法和最小二乘法可明显提高水下控制点垂直解的精确度.