海道测量中测线定位数据处理的三种模型

Three Models for Processing of Survey-Line Positions in Hydrographic Survey

为了对海道测量中测线定位精度进行评估,以及为补偿测线系统误差的需要,提出了实测定位折线模型,同时在利用小波降噪算法求得拟合航迹线的基础上,提出了拟合定位测线的概念,针对测线的不同形态给出了拟合测线的另外两种模型,即拟合直线和拟合折线。仿真实验表明:提出的三种测线模型均满足1:2 000以下比例尺测图要求;在满足定位精度和测线正横水深梯度不超限的约束条件下,可以用拟合测线代替原始测线进行数据的后处理;三种测线模型对系统误差不存在"淹没效应";拟合折线可以方便地减弱测线内受方向、船速等系统误差的影响。

For evaluating the precision of survey-line position and compensating survey-line system error in hydrographic survey, Measured-Position-Dogleg model （MPD）is proposed. Meanwhile, the Approximated-Course Line （ACL） concept is presented based on determining ACL with wavelet denoising algorithm, and two approximated survey-line models, namely Approximated Straight-Line （ASL） and Approximated-Dogleg Line （ADL）, are given according to the different survey-line forms. Results of the simulation demonstrate that： （1） the proposed models could all meet the mapping requirements under the scale of 1：2 000; （2） the approximated survey-line models can replace the original measurement lines to process survey-line position data under the condition that position precision and survey- line transverse depth gradient are well within the required limit of hydrographic survey norms; （3） the three survey-line models do not exert inundated-effect to the system error; （4） ADL can conveniently reduce the measuring line system error affected by course and boat speed.