On-Orbit Radiometric Calibration of High-Resolution Optical Satellite Camera Based on Wide Dynamic Targets

Aiming at site radiometric calibration is difficult to cover the dynamic range of the remote sensor, an on-orbit calibration method for high-resolution optical satellite camera is presented using wide dynamic targets with multiple linear reflectance (WDTMLR). It replaces the assumption of aerosol scattering characteristics with the actual measurement of ground synchronization. At the same time, the WDTMLR approach could isolate the response of wide dynamic targets from the response produced by sky path radiance, ground-atmospheric coupled radiance and dark current by using linear regression method, which simplifies radiometric transfer calculation and reduces the requirement of background. The WDTMLR method can achieve full dynamic calibration and linear measurement of spaceborne high-resolution remote sensing sensor. Results show that the uncertainty of the calibration approach is less than 3.6%. The difference in calibration coefficient between the WDTMLR method and the reflectance-based method is less than 5.5%. Moreover, the difference between the reflectivity and radiance of ground object obtained by the satellite sensor and that of field measured value is less than 6%, which demonstrate the effectiveness of on-orbit radiometric calibration. The WDTMLR method can satisfy with the application requirements for high-precision on-orbit calibration in complex environmental conditions.