卷云大气的红外辐射特性是空间光电探测系统的重要背景辐射源。基于2.7 μm和4.3 μm波段的卷云粒子散射特性参数, 建立了卷云大气辐射传输模型。在MODIS实测卷云和大气参数条件下, 仿真计算得到大气层顶的红外辐射图像。各像元辐亮度的统计结果显示: 在2.7 μm带的平均辐亮度为1.832e-2±3.024e-2 W/(m2·sr), 卷云像元平均辐亮度比晴空像元强433倍; 各像元在4.3 μm带的平均辐亮度为3.027e-2±2.99e-3 W/(m2·sr), 像元最大辐亮度是最小值的2.37倍。

Infrared radiance characteristic of cirrus atmosphere is the main clutter sources for advanced space-based electro-optical detecting systems. Based on bulk scattering parameters of cirrus particles in 2.7 μm and 4.3 μm wavebands, cirrus atmosphere radiance transfer model was constructed. With cirrus and atmosphere parameters measured by MODIS, the infrared radiation images of cirrus atmosphere were calculated. The statistical results of all pixels show that, in the 2.7 μm band, the average radiance is 1.832e-2±3.024e-2 W/(m2·sr), and the average radiance of cirrus pixels is 433 times larger than that of the clear-sky pixels; For 4.3 μm in-band radiance of all pixels, the average value is 3.027e-2±2.99e-3 W/(m2·sr), the maximum value is 2.37 times as large as the minimum.