直接修正大气实现小目标高精度辐射测量

Direct atmospheric correction for high precision radiometry on infrared small target

实现大气的传输修正是地基红外辐射测量系统获取目标真实辐射亮度的重要步骤之一，传统获取大气透过率和大气程辐射的方法是通过大气传输修正软件计算得到的。提出利用标准参考源实现大气修正，并将该方法实现对小目标的高精度辐射特性测量余反演。文中对宽动态范围的辐射定标模型和方法进行理论推导，实验采用600mm口径的辐射测量系统进行辐射测量验证。实验数据分析表明采用本文提出方法对小目标的辐射反演误差在0．97％～1．03％，而相比传统采用大气传输软件计算的辐射反演误差在7．3％～7．36％，因此所提出的方法具有更高的辐射测量与反演精度。

Atmospheric correction is one of important steps to obtain the intrinsic radiance of the target for an infrared radiometry system. Traditionally, the mean to calculate atmospheric transmittance and atmospheric path radiance are calculated by an atmospheric radiance transport calculation software, A method based on standard reference direct amending atmospheric attenuation was proposed, which was applied for high precision precision measurement and inversion on a small target. The based principle and procedure of this method were introduced, and then the model of wide dynamic calibration was employed. Radiometric experiments were performed on a mid-wave infrared system with a ~600 mm aperture. The radiometry results indicated that the radiance inversion precision for a small target, using the proposed method, is 0.97%-1.03%, while the precision using a conventional atmospheric transport calculation software method is 7.30%-7.36%, which demonstrates that the proposed method provides a high-precision result.