A Study On Scattering From Target And Rough Surface By Using FDTD Method

With the continuous development of the environmental remote sensing and radar detection technologies, we pay more and more attentions on the research of electromagnetic scattering with random rough surfaces and complex target. How to accurately establish the target and rough surface scattering model on the various incident wave conditions is an important goal of this kind of problem. In recent years, as the significant increase of computing power, more and more scholars take into the study of rough surface and objectives using numerical methods. In this paper, we use the FDTD numerical method to analysis the rough surface and the target on the electromagnetic scattering properties.On the introduction of the source, the paper has completed the two-dimensional and three-dimensional of introducing the incident wave at any angle in the whole space, the incident plane wave source is integrity and having no leakage. We deeply analysis of the model of the rough surface which of using the plane wave and window function method, and made further improvements, we introduce of a new methods to solve the rough surface problems on dealing with the new window function of the incident wave loading. The new incident wave loading method can guarantee a good behavior in any incident angle, the incident wave and the rough surface can be a very good action on the center of interaction region, greatly reducing the incidence wave directly leak to the side of the absorbing boundary. This new method is a good solution to solve the increases of the rough surface scattering calculations and reduce the accuracy of computation problems in the large angle oblique incidence case.The key of the problem to process the electromagnetic scattering is that the precise of the target grid partitioning and the correct of loading incident. Based on the AUTOCAD meshing tools, this paper presents a new method on mesh generation. The method makes full use of the existing three-dimensional drawing software partition function of the entity, and greatly reducing the time of target's mesh generation and improves the overall efficiency of the electromagnetic scattering calculations.