热红外传感器辐射响应影响机理与修正模型研究

HJ-1B/IRS传感器是目前我国民用航天领域中两颗具有热红外中空间分辨率(≥300m)的在轨传感器之一，具有巨大的应用需求。本项目以提高HJ-1B/IRS在轨辐射校正精度为目标，全面探索全光路成像系统随机性误差、中红外通道串扰和探元自身电子衰变三者耦合对热红外通道辐射响应的影响机理。通过对中红外和热红外各自探元在不同扫描线和不同帧之间的二维空间分布谱的建立、比对和排查，挖掘中红外通道串扰影响；结合随机性误差的特点把它概化为信号检测的奇异点，通过对长期基准黑体观测记录的离散小波变换分析，建立恰当的高通滤波器从频率域中分离随机性误差；通过对随机性误差和通道串扰效应的剥离，分析探元电子衰变与在轨运行天数之间的联系。最终，构建随着在轨运行时间的增长，耦合多源影响要素的传感器辐射响应综合修正模型，弥补当前常温和高温两点阶段性定标模式中辐射校正能力的不足，提高传感器在轨辐射校正精度和水平。

HJ-1B/IRS is one of the thermal infrared sensors of mid-spatial resolution(≥300m) for civil aerospace, which demonstrate of large application demand and capability. This study aims to enhance the radiometric calibration precision of HJ-1B/IRS, while discovers the cross-affection mechanism in the system random error, mid-infrared optical cross-talk and IRS detector itself degradation. Spatial spectrum is built, griddled and analyzed according to the scan line and frame of both mid-infrared and thermal-infrared to reveal the affection of optical cross-talk. Random error is abstract to singularity, and analyzed by little wave model to extract it from full-optical-chain based on its characters and optimal filter. After the extraction of cross-talk and random error, a relationship between thermal-detector degradation and on-orbit days is correlated. Finally a model relates to the coupling of on-orbit days, random error and cross-talk is established to correct the radiometric effects of these influence items. This model covers the shortage of the two-point calibration method, using a normal temperature and a high temperature, on the radiometric correction aspect to improve its precision and level.