Triple linear-array image geometry model of ZiYuan-3 surveying satellite and its validation

Abstract

ZiYuan-3 (ZY-3) surveying satellite is China's first civilian high-resolution stereo mapping satellite. The satellite's objective is oriented towards plotting 1:50,000 and 1:25,000 topographic maps. Compared with plotting using foreign commercial mapping satellite imagery, establishment of the image geometry model is the core technical problem for different products and various applications of ZY-3 surveying satellite. This article analyses key problems of high-precision geometry processing based on the overall design, and proposes ZY-3 surveying satellite image geometry model with the technology of virtual CCD line-array imaging. In addition, this article utilises the first orbit imagery of ZY-3 satellite with coverage of Dalian region in Liaoning Province, and produces forward, backward and nadir camera calibrated products. Different ground control points are selected for the block adjustment experiment and the digital surface model (DSM), digital ortho-map (DOM) are generated. The accuracy is validated by check points. The experiment reveals that the planar accuracy of DOM and vertical accuracy of DSM are better than 3 m and 2 m, respectively. The experiment demonstrates the effectiveness of ZY-3 surveying satellite image geometry model.

Keywords:

• ZY-3 surveying satellite
• image geometry model
• virtual CCD array
• block adjustment
• space intersection

Acknowledgements

The authors acknowledge Heilongjiang Administration of Surveying, Mapping and Geoinformation for GPS measurement of Dalian. They also thank Guo Li for her assistance in control points selection. They extend their gratitude to GEOWAY, Chinese Academy of Surveying and Mapping and China Academy of Space Technology for their support in software. This study was funded by National Natural Science Foundation of China (No. 40930532), National Science and Technology Support Programme (No. 2011BAB01B01, No. 2011BAB01B02, No. 2012BAH28B04 and No. 2011AA120404) and National Defense Science and Technology Programme ‘Research on key technologies of data processing, application and in-orbit testing for ZY-3’.