基于大气程辐射比例修正的红外辐射特性测量

摘要

大气程辐射是影响目标红外辐射特性测量精度的重要因素之一.本文利用大气程辐射修正因子修正大气程辐射值以提高其测量精度.首先,给出目标红外辐射特性测量模型,然后,提出利用大气程辐射修正因子的目标红外辐射特性测量方法.该方法将一定距离下实际测量的大气程辐射和MODTRAN计算的大气程辐射之比定义为大气程辐射修正因子,最后利用该修正因子对其他距离的MODTRAN计算的大气程辐射进行修正并进行目标的辐射反演,获得目标辐射特性.本文利用中波红外摄像机和小面源黑体开展目标红外辐射特性测量实验.实验结果表明,本文方法较传统方法可以在一定程度上提高目标辐射特性测量精度,将精度提高2%左右.%Atmospheric path radiation is one of the important factors affecting the measurement precision of target in-frared radiation characteristics.The atmospheric path radiation was corrected by using correction factor to improve the measurement precision.Firstly,the measuring model of target infrared radiation characteristics was established.Then, the measuring method of target infrared radiation characteristics based on the correction factor of atmospheric path ra-diation was proposed.The ratio of the really-measured atmospheric transmittance at a certain distance and the one cal-culated by using MODTRAN is called the correction factor of atmospheric path radiation.Finally,the atmospheric path radiations calculated by MODTRAN at other distances were corrected by the correction factor,and target radiation was inversed to obtain target radiation characteristics.Some measuring experiments of target infrared radiation characteris-tics were performed by using a medium wave infrared camera and a black body.The results show that the radiation measuring precision obtained by using proposed method is improved comparing with that obtained by using the conven-tional method.The precision is improved about 2%.