Hiding a Bump on a PEC Plane by Using an Isotropic Lossless Dielectric Layer

An infinite perfect electric conducting (PEC) plane on top of which lies a 2-D PEC object (bump) is excited by a plane wave. The main purpose of this work concerns the determination of the appropriate permittivity εr and thickness H of a lossless dielectric superstrate slab layer, placed on top of the overall structure of the PEC bump and the PEC plane, such that two objectives are fulfilled: 1) the plane wave reflection by the grounded slab configuration in the absence of the bump resembles closely that by the infinite PEC plane, and simultaneously 2) the contribution due to the presence of the bump itself on the scattered far-field radiated over all directions becomes as small as possible. A semianalytic integral equation methodology is developed to determine the field scattered by the bump configuration. Numerical results are presented demonstrating that indeed for certain regions of values of the superstrate´s parameters both objectives 1) and 2) are met within significant numerical accuracy. Particularly, it is shown that may offer optimal cloaking characteristics. Finally, the results of the analysis as well as of the developed two objectives strategy are verified by appropriate computational simulations.