High Accuracy On-orbit Geometric Calibration of Geostationary Satellite GF4

GF4 satellite is the first high resolution optical geostationary satellite for remote sensing in the world, and the high accuracy geometric calibration is the key factor for the geometrical quality of satellite imagery. The positioning errors and the features of imaging region of GF4 were analyzed, the rigorous imaging model was introduced. Then on orbit calibration model and parameters estimation method were introduced for planar array sensor of GF4 satellite. The experiments used the DOM of Landsat 8 and DEM of GDEM2 for the on-orbit calibration, and the results indicated that internal accuracy of the panchromatic and near-infrared sensor and intermediate infrared sensor can be stably better than 1 pixel in the along and vertical track direction, and the absolute positioning accuracy of GF4 would be greatly affected by imaging time and imaging angle, and fluctuated remarkably.