Numerical Scattering Analysis for Two-Dimensional Dense Random Media: Characterization of Effective Permittivity
نویسندگان
چکیده
In this paper, a new numerical method for determining effective permittivity of dense random media in two dimensions is presented. The core of the method is to compare the average scattered field of a random collection of scatterers confined within an imaginary boundary with the scattered field from a homogeneous dielectric of the same shape as the imaginary boundary. The two-dimensional (2-D) problem is aggressively studied here to provide insight into the dependence of the method’s convergence on particle size, boundary shape, and boundary dimension. A novel inverse scattering method is introduced based on the method of moments (MoM), which greatly reduces the computation time and increases the flexibility of the procedure to analyze a variety of geometries. Results from this 2-D method may be used directly to compare with theoretical methods for determining effective permittivity such as the Polder–Van Santen mixing formula or field techniques such as the quasi-crystalline approximation.
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