Study on Radiometric Calibration of FY-2H Satellite Based on Site Measurement and Reference Image

Abstract

The on orbit radiometric calibration of remote sensor is the key to characterize the characteristics of remote sensor. FY-2H satellite, a newly launched stationary meteorological satellite in China, has strong application value in weather, climate and ecological environment monitoring. In order to analyze which method can obtain high-precision FY-2H calibration coefficient, this paper takes Dunhuang Calibration Field as the research area and FY-4A satellite as the reference image to carry out cross radiometric calibration in the visible band. At the same time, the on orbit site calibration is realized based on the measured synchronous data and multi-day average data, and the relative differences of calibration coefficients of different methods are calculated. The impact of BRDF is also analyzed. The results show that the relative difference of calibration coefficient of cross calibration on different dates is 0.52%, and the relative difference of two site calibration methods is 5.11% and 3.61%; After BRDF correction, the average relative difference can be reduced from 15.72% to 6.97%. The research shows that the cross calibration method is better than the other two site calibration methods for the VISSR sensor of FY-2H satellite.