天空大气背景红外辐射建模与计算

摘要

研究天空大气背景的辐射对空中目标的探测非常重要,为此对大气辐射亮度的计算进行了建模与计算,通过对大气分层的方法得到了天空辐射亮度的计算公式,然后结合公式对吸收和散射的计算方法进行了详细的讨论,对于吸收主要考虑了水蒸气、二氧化碳和臭氧的吸收,而散射主要讨论了气溶胶的散射,最后通过典型数据对大气吸收、散射、透过率、光谱辐射亮度、辐射亮度等进行了计算,与MODTRAN软件的计算结果进行了比较,并对天空红外辐射的特点进行了分析.%For aerial target detection,it is highly important to study the radiance of sky background.The model and method for calculating the radiance of sky are set up.The calculating formula is established by layered atmosphere.Combined with the formula,the calculating of absorption and scattering is discussed in detail.The absorption of vapor,carbon dioxide,ozone and the scattering of aerosol are mainly considered.At last,the absorption,the scattering,the transmission,the spectral radiance and the radiance of sky are calculated by typical data,furthermore,the results are compared with MODTRAN.And the features of the sky infrared radiation are analyzed.