Numerical analysis of scattering from 3-D dielectric objects buried in a dielectric medium using the Yasuura method

We apply the Yasuura method to numerical analysis of scattering from 3D dielectric objects buried in a dielectric half space. We solve this problem using the Yasuura method, we take into account the effect of the plane interface between air region and land. We use the refracted plane wave and reflected scattered wave at the plane wave as incident wave. Then the problem can be treated as a conventional scattering problem in a homogeneous medium. The reflected electromagnetic fields are represented by multipoles which are arranged in a symmetrical position to the plane interface. By minimizing the discretized squared norm about the boundary condition at the surface of the scatterer with respect to the expansion coefficients, we can calculate the scattered fields. After checking the accuracy of the numerical solution, we show several numerical examples. It is found that the dominant part of the scattered pulses form the buried object and a refracted-diffracted pulse for the perfectly conductor or an internally refracted-reflected pulse and a diffracted-refracted pulse for the dielectric object.