A Rigorous on-orbit Geometric Calibration Method for High-Resolution Optical Sensor of Chinese Mapping Satellite

Internationally, the technology of optical earth observation satellite is developing in the direction of miniaturization, high-resolution and high maneuverability. High-precision on-orbit geometric calibration of the imaging sensors is the most important guarantee of interior geometric quality and direct positioning accuracy of the satellite images. The high-resolution camera of Chinese Mapping Satellite-1 is a multi-chip TDICCD optical sensor in triangular mechanical staggered stitching structure. To improve the accuracy and robustness of its geometric calibration while reducing the correlation between calibration parameters, this paper proposed a new multi-chip pointing angle model for internal calibration and an optimized imaging model for external calibration. The overlapping connection relation between multi-chip TDICCDs of an image and multi-scene images are fully utilized for constructing the calibration error equations with constraints. Then, the internal and external calibration are iteratively solved through relaxation block adjustment method. Experimental results demonstrate that the proposed rigorous on-orbit geometric calibration method can effectively and stably eliminate various system errors of the imaging system, thus improving the interior and exterior geometric quality of image production.