Points The Boundary Element Method And Parameters Inversion Of Rough Surface Scattering

scattering from a rough surface has very wide applications, such as radar cross section from sea and land surfaces, undestructively probe the surface of natural and artificial products, and so on. There are many approaches to solve scattering from rough surfaces, such as KAM (Kirchhoff Approximation Method) , SPM (Small Perturbation Method), two of the two-scale method, and Rayleigh method. Fractal geometry discussed the self-similarity distribution of the fractal structure, and took into account random rough surface the characteristics of ordered in large-scale and disordered in small-scale, so it is more close to the real surface. Fractal function only with a little number of parameters can describe complex objects.The finite element method (FEM) and the boundary element method (BEM) are two importantmothods solve nonlinear partial differential equations. FEM has been used to study scattering from the rough surface. However, BEM has more advantages. We can get (?)u/(?)n directly from BEM.But we must use poor to replace (?)u/(?)n and will get a greater error due to the instability of the poor.This article discuss the inverse problem of fractal paramter D. Minimum objective function method is applied in this paper. we select D = 1.1, ? ? ? ,1.9 these nine groups to discuss the greatest error and the average error and iterative step. When b, n, zO, L, d change have little effection to the results of the inversion. Finally, the the inversion results are impacted by Observations are small disturbances.This article also discussed the double parameters inversed problem. We select fractal parameters D and b are inversed objection. Calculated of the multi-group results, discussed the biggest error and the average error . When 6, n, zO, L, d change have little effection to the results of the inversion. Finally, the the inversion results are impacted by Observations are small disturbances.