高层大气环境对长波红外背景辐射特性的影响分析

高层大气长波红外背景辐射特性是目标识别和红外辐射特性测量的重要研究课题.根据NRLMSIS-00大气经验模型,分析了高层大气温度和气体浓度对红外辐射的影响.利用高层大气辐射传输模式SHARC,在6～15 μm波段对不同观测位置和大气模式条件下的高层大气背景辐射进行了数值计算和理论分析.结果表明,高层大气长波红外辐射会随临边切线高度的增加而减弱,随倾斜观测天顶角的增加而增强,随太阳天顶角的增加而减弱.曙暮光和极光对高层大气长波红外辐射具有重要的增强作用,而且高层大气长波红外辐射存在纬度和季节变化特性.高层大气环境对长波红外背景辐射的影响分析结果可供空间目标探测和卫星红外遥感等工程参考.

Influence of Upper Atmospheric Environment on Long-wavelength Infrared Background Radiation

The characteristics of long-wavelength infrared background radiation from upper atmosphere are the important research topics for target recognition and infrared radiation characteristic measurement. According to the NRLMSIS-00 empirical atmosphere model, the influence of the temperature and gas concentration of upper atmosphere on infrared radiation is analyzed. By using SHARC, the upper atmospheric radiance code, the upper atmospheric background radiation in different observation positions and different atmospheric modes is calculated numerically and analyzed theoretically in the waveband from 6 m to 15 m. The result shows that the long-wavelength infrared radiation of upper atmosphere can be attenuated with the increase of limb tangent height, can be enhanced with the increase of observation zenith angle and can be attenuated with the increase of solar zenith angle. The aurora and twilight are of importance to the enhancement of the upper atmospheric long-wavelength infrared radiation and the upper atmospheric long-wavelength infrared radiation can be varied with the change of latitude and season. This analysis is of reference value to the space target sensing and infrared remote sensing.