FY-3E/HIRAS-Ⅱ发射前热真空定标试验非线性校正  

Nonlinearity correction of FY-3E HIRAS-Ⅱ in pre-launch thermal vacuum calibration tests

作　　者：杨天杭 顾明剑[1,2] 邵春沅 吴春强[4] 漆成莉[4] 胡秀清[4] YANG Tian-Hang;GU Ming-Jian;SHAO Chun-Yuan;WU Chun-Qiang;QI Cheng-Li;HUXiu-Qing(Key Laboratory of Infrared System Detection and Imaging Technology,Chinese Academy of Sciences,Shanghai 200083,China;Shanghai Institute of Technical Physics,Chinese Academy of Sciences,Shanghai 200083,China;National Laboratory for Infrared Physics,Shanghai Institute of Technical Physics,Chinese Academy of Science,Shanghai 200083,China;Key Laboratory of Radiometric Calibration and Validation for Environmental Satellites,National Satellite Meteorology Center,China Meteorological Administration,Beijing 100081,China)

机构地区：[1]中国科学院红外探测与成像技术重点实验室,上海200083 [2]中国科学院上海技术物理研究所,上海200083 [3]中国科学院,上海技术物理研究所红外物理国家重点实验室,上海200083 [4]国家卫星气象中心,中国遥感卫星辐射测量和定标重点开放实验室,北京100081

出　　处：《红外与毫米波学报》2022年第3期597-607,共11页Journal of Infrared and Millimeter Waves

基　　金：国家重点研发计划项目(2018YFB0504800,2018YFB0504800)。

摘　　要：红外高光谱大气探测仪Ⅱ型(HIRAS-Ⅱ)是一台傅里叶变换光谱仪,搭载于世界首颗民用晨昏轨道气象卫星FY-3E上,其研制过程在FY-3D/HIRAS-I产品基础上,重点提升了探测器灵敏度、光谱和辐射定标精度等方面。仪器发射前进行了全面的热真空定标试验,其中非线性订正作为辐射定标过程的重要环节,对辐射定标精度具有重要影响。针对HIRAS-Ⅱ长波和中波1红外探测器产生的非线性效应,通过缩放带内光谱对原始数据作非线性订正,采用最小化不同温度点复原光谱各波数点的响应度分布和最小化变温黑体定标偏差分布两种方法推导非线性系数。对比辐射定标数据作非线性订正前后的光谱亮温偏差,结果表明,经过非线性订正后的辐射定标精度得到了明显提升。The High-spectral Infrared Atmospheric SounderⅡ(HIRAS-Ⅱ)is a Fourier transform spectrometer onboard the world’s first civil early-morning-orbiting FengYun 3E(FY-3E)meteorological satellite,the FY-3E/HIRAS-Ⅱfocus on a number of upgrades such as the sensitivity of the detector,the accuracy of spectral calibration and radiometric calibration,with the designed and manufactured processing based on the first Chinese hyperspectral infrared(IR)sounder FY-3D/HIRAS-I.We conducted a comprehensive pre-launch thermal vacuum(TVAC)calibration tests for HIRAS-Ⅱ,including the nonlinearity(NL)correction which consists an essential part of radiometric calibration,the NL correction has considerable effects on radiometric accuracy.According to the HIRAS-Ⅱnonlinear behavior of the detectors for long-wave(LW)and mid-wave1(MW1)infrared spectral bands,the NL correction of raw data in the spectral domain is a scaling of the observed spectrum,the NL correction coefficients are derived by the methods of minimizing the spread of the responsivity of reconstructed spectrum in each wavenumber with varying temperature,or minimizing the spread of the bias of brightness temperature among calibration targets with varying temperature.The bias of spectral brightness temperature is assessed by comparing the NL correction and the non-NL correction radiometric calibration data,the results show that,the radiometric accuracy has been significantly improved via NL correction.

关 键 词：HIRAS-Ⅱ 非线性校正 辐射定标 热真空试验 

分 类 号：TN215[电子电信—物理电子学]