基于冰雪场景的大视场遥感器在轨辐射定标方法  

Research on On-Orbit Radiometric Calibration Method for Remote Sensors with Large Fields of View Based on Snow and Ice Scenes

作　　者：潘雨薇 陈斐楠 骆冬根 孙亮 王羿 纪峰[2] 陈晶晶[2] 洪津[1] Pan Yuwei;Chen Feinan;Luo Donggen;Sun Liang;Wang Yi;Ji Feng;Chen Jingjing;Hong Jin(Anhui Institute of Optics and Fine Mechanics,Hefei Institutes of Physical Science,Chinese Academy of Sciences,Hefei230031,Anhui,China;School of Instrument Science and Opto-Electronics Engineering,Hefei University of Technology,Hefei 230009,Anhui,China)

机构地区：[1]中国科学院合肥物质科学研究院安徽光学精密机械研究所,安徽合肥230031 [2]合肥工业大学仪器科学与光电工程学院,安徽合肥230009

出　　处：《光学学报》2023年第18期315-326,共12页Acta Optica Sinica

基　　金：高分专项(民用部分)卫星应用共性关键技术项目(50-Y20A38-0509-15/16);卢嘉锡国际合作团队项目(GJTD-2018-15);国家自然科学基金(11504383)。

摘　　要：场景定标是大视场遥感器在轨替代定标的常用方法,具有定标频率高、无需同步测量的优点。冰雪场景通常使用格陵兰冰盖(75°S,123°E)和南极冰盖(73.375°N,40°W)作为目标,由于其海拔较高(通常大于2km),故受到大气影响较小,能够得到数据质量较好的定标样本。此外,冰雪在可见光范围以内光谱较为平坦,因而比较方便借助于其他定标方法实现波段传递。基于对前人极地场景定标方法的研究,将冰雪场景的地表双向反射分布函数(BRDF)和大气参数代入辐射传输模型之后,对我国高分五号卫星大气气溶胶多角度偏振探测仪(DPC)载荷的在轨辐射响应变化进行测试,得出的结论与沙漠场景和海洋场景的定标结果吻合度较高,且定标结果的离散度更小。所提方法可以对载荷在轨运行期间的探测数据提供长期监测、校正,并有助于业务化应用产品的质量提升。Objective Radiation calibration is a necessary prerequisite for the quantification of remote sensing data from laboratory calibration before launch to on-orbit calibration after launch throughout the entire life cycle of remote sensors.Site calibration is a common method for on-orbit alternative calibration of remote sensors with large fields of view.When a remote sensor is operating normally,it is calibrated with a large area of uniform ground objects as the calibration source,which has the advantages of a high calibration frequency and no need for synchronous measurement.The Greenland ice sheet(-75°S,123°E)and the Antarctic ice sheet(73.375°N,-40°W)are commonly used as targets for snow and ice scenes,whose surfaces are covered with evenly distributed snow.Due to their high altitudes(usually greater than 2 km),they are less affected by the atmosphere and help obtain calibration samples with better data quality.Furthermore,ice and snow have a relatively flat spectrum in the visible range,which makes band transfer easier with other calibration methods.Thus,using the Greenland ice sheet and the Antarctic ice sheet as the calibration source of snow and ice scenes has many advantages for the calibration and verification of remote sensors.Methods The research method in this paper is based on the previous study of polar scene calibration methods.First,we choose Greenland as the calibration target of snow and ice scenes and select the calibration sample in the directional polarimetric camera(DPC)level 1 data.The area interfered with by cloud pixels is then eliminated after spectral channel traversal and angle traversal through the calibration sample's rows and columns.After substituting the surface bidirectional reflectance distribution function(BRDF)and atmospheric parameters(aerosol,water vapor,ozone,and other profiles)of the snow and ice scene into the radiative transfer model to obtain the zenith reflectivity and radiance,we test the on-orbit radiation response changes of the payload of the DPC on Gaofen-5 satel

关 键 词：在轨辐射定标 冰雪场景 辐射传输 地表双向反射分布函数模型 

分 类 号：P407.4[天文地球—大气科学及气象学]