Conformal and confocal mantle cloaking of elliptical cylinders using sub-wavelength metallic meshes and patches

In this paper, we present a conformal mantle cloak design in order to realize the invisibility of dielectric and conducting elliptical cylinders using 2-D sub-wavelength metallic meshes and patches. Although the electromagnetic wave scattering of an elliptical cylinder is pertinent to the angle of incidence, it is shown that the cloak design is robust for any incident angle. The scattering behavior of the cloaked objects is analyzed by expressing the incident and scattered fields in terms of radial and angular Mathieu functions and applying sheet impedance boundary conditions at the interface of the sub-wavelength elements.