中国遥感卫星辐射校正场以青海湖水面作为遥感卫星红外探测通道外场辐射定标的场地.我国静止气象卫星风云二号(FY-2)系列是自旋稳定卫星,其红外通道无法进行在轨时的星上绝对定标,而青海湖对于位于东经105°赤道上空的FY-2卫星来说,卫星天顶角有36°,超过了外场辐射校正测量规范要求.本文介绍了利用我国南海海面水体辐射,进行与静止气象卫星的同步测量试验,开展卫星红外通道在轨外场辐射定标处理的可行性研究.在分别对FY-2B与FY-2C的测量数据处理后,初步确定我国南海海面可以作为我国静止气象卫星在轨辐射定标的场地.
The water surface of Qinghai Lake which is one of China Radiometric Calibration Site of remote sensing satellite (CRCS) is used as the field of radiometric calibration for the infrared channel of remote sensing satellites. As our spin-stabilized geostationary meteorological satellites, FY-2' s infrared channel can' t realize an absolute calibration on orbit.. Since FY-2 is located at the equator of 105 degrees east longitude to Qinhai Lake , the satellite zenith angle is 36 which is larger than the measurable range of the criterion for radiometric calibration site. This study describes a method to calibrate the infrared channels of geostationary meteorological satellites based on the simultaneous measurement of upwelling sea-surface radiance in the South China Sea. The data analysis for FY-2B and FY-2C shows that the South China Sea is a suitable radiometric calibration site for geostationary meteorological satellites.