Underlying Surface In Surface-to-air Observations, And The Sky Background Simulation Software Development

Modern war not only needs great ability of attacking, but also needs perfect ability of assistant, which means having a sensor that can destroy enemy's missile or its guiding system exactly and real-timely. But the most important problem is that finding and recognizing the object from the complex background.Surface, as atmosphere and cloud, is one of factors which impacts the ground-to-air observation. So, researching the influence causing by surface is necessary. And that is what the work of this paper does. It is a branch subject of the national natural science fund project called the model and emulating about the property of spectrum radiative in sky background. The whole project can be divided into 3 parts: the radiative transfer in atmosphere, the radiative transfer in cloud and the radiative transfer on surface.The third part is the research of this paper. From the content of the paper, it can be made of two parts: One is the radiative transfer on surface, and the other is the designing of the emulating-software on sky background.According to above two parts, the first part is mainly about the Lambort-surface, such as sea, desert and so on. Based on no-changing principle in radiative transfer theory and the model which is obtained by the world standard, the expression about the radiation caused by surface is concluded.Then, the two key parameters are calculated with relative theories. First is diffusion permeation: the theory about the calculating approximating of diffusion permeation in limited medium by Roujean is used, and the four fluxes used in non-Lambort-surface are also introduced. Second is reflectivity: Issaacs Double-streams approximating, Eddington approximating, C-C double - streams approximating,δ- Double-streams approximating andδ- Eddington approximating is explained and used to calculate the reflectivity. At last, the two parameters is used in the above model to obtain the result. And this result is compared with that of Modtran, which is tally with it. Also, the changing trend of radiation to certain wavelength is...