Analysis of Size and Orientation of Apertures for H-polarized Plane Wave Electromagnetic Scattering by Concentric Perfectly Conducting Circular Strips

This study aims to investigate the diffraction of electromagnetic plane waves generated by two concentric cylinders with slits placed at different positions. Unlike previous studies, this study investigates the previously unstudied rotational resonance characteristics and how they affect the near-field distributions. This analysis considers the diffraction for H-polarized plane waves. A semi-analytical approach is adopted to determine the basic physical properties such as resonances, near- and far-field radiation patterns. This method benefits from the integration of both analytical and numerical techniques. Since H-polarized waves are investigated, the Neumann boundary condition is applied and analyzed accordingly. After deriving the mathematical formulations for the current density, near- and far-field distributions, and total radar cross section, the results are compared with those obtained by the Method of Auxiliary Sources (MAS). The comparison confirms that the proposed approach is in good agreement with this established technique. The findings show that both the size of the apertures and the rotation angle play an important role in determining the radiation characteristics.