Validation for the absolute radiometric calibration of the HJ-1B CCD sensors of China

On September 6, 2008, the satellite HJ-1B was launched into a sun-synchronous, near-polar orbit. In order to determine temporal changes of the absolute radiometric calibration of the HJ-1B satellite in flight, a program was carried out at DunHuang calibration field, Gansu province of China, from August 19 to 30, 2009. In this work, reflectance -based calibration method was employed to simulate the absolute calibration coefficients of the HJ-1B CCD sensors. Then the cotton field, cement court, water pool and test site was selected to validate the calibration coefficient. The validation results indicated that there had a good agreement between the imaged-based reflectance and the ground measurement of the type of cement court and test site. On the other hand, there had a disagreement of the type of cotton field and water because of the effect of mixed pixel.