On the Scattering Analysis Methods of and Reflection Characteristics for an AMC/AEC Surface

Abstract

This paper initially presents an analysis of the electromagnetic scattering from a grounded dielectric slab loaded by a periodic conducting-strip grating using Floquet's modal expansions. The analysis treats any incident wave in an arbitrary plane, and having arbitrary angle and polarization. Explicit expressions are derived for the reflection coefficients of all harmonic modes. It is shown that this method is equivalent to the Galerkin Method of Moments (MoM) in the spectral domain. This means both methods result in the same matrix equation to be solved for the coefficients of the surface-current-density basis functions. Next, using this analysis method, the effects of various parameters on the reflection-coefficient phase of the aforementioned periodic structure is thoroughly studied. The parameters studied include the widths, dielectric permittivities, and thicknesses of the strips, as well as the plane, angle, and polarization of the incident wave. This parametric study shows that this structure can act as either an artificial magnetic conductor (AMC) or an artificial electric conductor (AEC), depending on the angle, polarization, and plane of the incident wave. However, the structure may not be able to maintain the distinct characteristics of an artificial magnetic conductor or an artificial electric conductor for all planes, angles, and polarizations of the incident wave. Some of the results are compared to the those obtained by commercial software packages, such as Ansoft's HFSS and Designer.