Study Of Electromagnetic Scattering From Sand

The research on electromagnetic scattering characteristics of sand surface has important scientific significance in ground environment remote sensing monitoring and target recognition. It is alse the important method to improve the imaging detection system performance and to test identification algorithm. This paper mainly studied electromagnetic scattering characteristics of several sand surfaces. The main works are as follows:The formation mechanism of sand ripple and movement models of grains of sand are described in the paper. The sand surface are simulated according to Nishimori-Ouchi’s and MiaoWuMu’s discrete models of surface evolution. And then, the article gave briefly the method of creating sand surface using the digital elevation model(DEM) data which is based on the system of geographical information system(GIS).The paper investigated the electromagnetic scattering problem of different two-dimensional sand surfaces mainly using kirchhoff approximation(KA) method and small slope approximation(SSA) method. Based on the kirchhoff approximation method, the backscattering coefficients and bistatic scattering coefficients of sand surface are calculated,which is shaped from movements sand saltation and creep movement from flat sand surface. Meanwhile, electromagnetic scattering coefficients are calculated using the small slope approximation method from surfaces of some typical small dune.Finally, Simulation of scattering cross section for sand surface is investigated in the paper, which are based on an hybrid model of revised KA model and γ-f model for backscattering coefficient and based on the datas of DEM of desert scene. The spatial distribution chart of RCS obtained by the model demonstrate that the results coincide with special terrain features and periodic characteristics of the desert scene. The validity of the model is then obtained.