Research On Earth Limb Background Infrared Radiation Characteristic

In modern military war, the pace of building air and space defense system is moving forward, infrared radiation characteristics of ballistic missiles and other aircraft become an important research direction. Infrared radiation characteristics of the aircraft not only its own radiation characteristics related to the environment and their background also closely linked, Therefore, the need for satellite infrared remote sensing aircraft background related research.Factors affecting aircrafts infrared radiation characteristics are mainly earth surface radiation and atmospheric radiation which make up the earth and limb background. In earth-atmosphere observation system, the earth background is composed of earth-surface and atmosphere simultaneously, and the limb background is consists of atmosphere only. In view of the differences of limb background and earth background, This paper established a limb atmospheric radiation imaging model, Expand research on the long wavelength infrared typical, and the preparation of relevant radiation calculation software is based on the findings.Firstly, based on limb Atmospheric infrared radiation background geometric model and calculation model, Establish a limb atmospheric background radiation imaging model, and Combined with the global, regional atmospheric properties, using MODTRAN infrared radiation calculation software to calculate the model under different conditions of season and latitude limb atmospheric background radiation. Including 3-5?m and 7.7-9.5?m two bands of infrared radiation detection wavelength region typical numerical characteristics, and analysis of the major factor that impact the limb background's infrared radiation characteristic are: tangent altitude, latitude, season, aerosols and bands.Secondly, using the MODIS data provided by NASA, the use of split window algorithm calculated the surface temperature inversion data in the year 2012 worldwide, based on this, Combined with surface type and surface type parameters covering the spectral curve, calculated surface emissivity of a typical band emission rate data; on the basis of the Earth background infrared radiation model of global surface radiation data is calculated based on the surface temperature and emissivity, MODTRAN combined radiation calculation model calculated global atmospheric transport of radiation, the Earth will be a combination of both backgrounds.The infrared radiation simulation results showed a typical feature of the earth and limb background, and received its main influencing factors, and laid a foundation for the infrared remote sensing of earth and limb background.