基于高光谱自动化观测设备的高分二号卫星在轨定标应用与验证

In-orbit calibration application and verification of Gaofen-2 satellite based on hyperspectral automatic observation equipment

为验证高光谱自动化野外观测设备的地表反射率数据的应用效果,基于反射率基法开展了高分二号(GF-2)卫星遥感器的在轨定标数据应用及验证。首先系统介绍了设备安装定标场的状况及多种自动化观测设备的工作方式及性能指标,并给出了仪器的观测数据及地表反射率数据的计算方式。随后结合GF-2卫星遥感器定标的需求并利用卫星大气数据产品和GF-2遥感器的同步过顶观测影像,完成了GF-2多光谱相机(PMS)遥感器的在轨定标。最后根据获得的定标系数,利用不同时段的遥感器影像数据进行了验证。两种不同地表的应用验证表明,卫星表观辐亮度的数据整体相对偏差优于2%,验证了高光谱设备在卫星遥感器在轨定标上的可行性。

In order to verify the application effect of surface reflectance data of hyperspectral automatic field observation equipment,the application and verification of in-orbit calibration data of Gaofen-2(GF-2)satellite remote sensor are carried out based on the reflectance-based method.Firstly,we systematically introduces the calibration field and the working mode and performance index of various automatic observation equipment,and demonstrates the calculation method of observation data and surface reflectance data of the instrument.Then,regarding to the calibration requirements of GF-2 satellite remote sensor,the in-orbit calibration of GF-2 panchromatic and multi-spectral(PMS)remote sensor is completed using satellite atmospheric data products and synchronous observation images of GF-2 remote sensor.Finally,based on the obtained calibration coefficients,the image data of remote sensors in different time periods are verified.The application verification of two different land surfaces shows that,the overall relative deviation of satellite apparent radiance is better than 2%,which verifies the feasibility of hyperspectral equipment in the in-orbit calibration of satellite remote sensors.