Simplified N-Sided Irregular Polygonal Ground Plane Cloak Created with Oblique Layered Isotropic Dielectrics

Abstract

Although different coordinate transformations could be utilized to design invisibility cloaks, in this work, we propose a straightforward way to design arbitrary-shaped ground plane cloak, in which only the y-coordinate is transformed in a uniform linear manner within the cloak area. Based on the proposed general way, an arbitrary N-sided irregular polygonal cloak can be designed, which is made up of N blocks, and each block only requires a simple homogeneous anisotropic material. To realize the proposed cloaks, layered grating systems are utilized to implement the blocks and demonstrate the overall performance of cloaking. Each grating system is constructed by two kinds of alternating isotropic dielectrics, and the alignment angles are determined by effective medium theory. Three parameter settings of the layered grating system are utilized for TM wave cloaking and hybrid wave cloaking. Each proposed makeup block of the N-sided polygonal cloak consists of alternating isotropic dielectric layers, thus can lead to an easy practical fabrication.