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The full current thin dielectric sheet (TDS) approximation is considered for the problem of electromagnetic (EM) scattering by a three-dimensional (3-D) homogeneous thin chiral dielectric sheet. This approximation leads to surface integral equations (SIE) instead of the traditional volume integral equations (VIE). The surface of the thin dielectric region is modeled by triangle cells. Consequently, the number of unknowns is reduced by only surface meshes being utilized to discretize the dielectric geometry. Modified Rao-Wilson-Glisson (RWG) and pulse functions simultaneously for basis and testing functions are employed to approximate the tangential and normal currents in the dielectric layer. Then these SIEs are solved numerically using the conventional method of moments (MoM). The results by this approach show agreement with other methods while it greatly reduces the number of unknowns.

The vector parabolic equation method was widely used to analyze the electromagnetic scattering from electrically large PEC objects in free space. In this paper, it is applied for the analysis of the electromagnetic scattering from PEC objects in halfspace. By introducing both the incident field and the reflected field to illuminate the objects, the vector parabolic equation method can be used to efficiently calculate the radar cross-section of PEC objects with electrically large size in half-space. The numerical results demonstrate that the proposed method can efficiently give reasonably accurate results.

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The analysis of chiral materials has been an important subject in computational electromagnetics. In this paper, the method of moments technique is used to solve the problem of transmission through an arbitrarily shaped aperture separating air and a chiral medium. The aperture is in an infinite PEC (perfect electric conductor) plane. The excitation is assumed to be a plane wave in air. The equivalence principle is used to replace the aperture with a conducting surface with an equivalent magnetic current on each side of it. By enforcing the continuity of the tangential components of the total electric and magnetic fields across the aperture, coupled integral equations are obtained. The aperture has been modeled by triangular patches. The equivalent magnetic currents are approximated by linear combinations of expansion functions. The mixed potential formulation for a homogeneous chiral medium is used to obtain the electric and the magnetic fields produced by these expansion functions. The coefficients of these expansion functions are obtained by using the method of moments to solve the coupled integral equations.