我国陆地区域似大地水准面对数字化测图的适用性分析

Applicability analysis of regional quasi-geoid model in land area of China for digitizing mapping

全球导航卫星系统(GNSS)与区域似大地水准面能够代替低等级水准测量,获取正常高成果。为服务于各省不同比例尺测图项目,本文分析我国陆地区域似大地水准面对数字化测图的适用性。首先,统计国内各省(市)的区域似大地水准面精度情况;然后,推导不同比例尺测图中,似大地水准面模型为满足不同地形类别下高程点的限差应达到的精度。结果表明,大多数省(市)的区域似大地水准面模型均优于±0.1 m,能够满足中大比例尺测图需要,可以为各省开展不同比例尺测图提供技术服务。

The low order leveling can be replaced by global navigation satellite system(GNSS)and regional quasi-geoid to obtain the normal height.In order to serve the different scale mapping projects of provinces,the quasi-geoid applicability analysis of digitizing mapping in land area of China is analyzed in this paper.Firstly,the model of the regional quasi-geoid is introduced and the accuracy of the quasi-geoid model in different scale mapping is derived to meet the limit difference of elevation points under various terrain categories.Secondly,the accuracy of the regional quasi-geoid is counted for provinces.The result shows that the accuracy of most quasi-geoid is better than±0.1 m,it is shown that most quasi-geoid could meet the requirement of different resolution digital mapping,and provide the service for mapping in provinces.