Overseas Mapping and Accuracy Evaluation Based on Zy -3 Satellite Imagery

The lack of control points is one of the main difficulties in overseas high-precision remote sensing mapping. The production test of basic surveying and mapping products without control points is carried out in a foreign country by using the image data of ZY -3 satellite. Temporary reference stations are introduced to produce basic surveying and mapping products with control points to verify the accuracy of surveying and mapping products without control points. According to statistics, under uncontrolled conditions, the plane accuracy of the stereomodel reaches ±11.23m, and the elevation accuracy reaches ±2.47m, the plane accuracy of the Digital Orthophoto Map (DOM) is ±3.75m, and the plane accuracy of the Digital Line Graphic (DLG) is ±4.11m, Digital Elevation Model (DEM) with an elevation accuracy of ±3.15m. The results show that under the complex terrain conditions of a foreign country, the uncontrolled point mapping of ZY -3 satellite images can meet the requirements of high-precision map production at a scale of 1: 25,000. The research results can provide technical reference for overseas rapid mapping under similar conditions and serve the national Belt and Road strategy.