Dielectric multilayers for antenna and cloaking devices designed from transformation electromagnetics

Transformation electromagnetics provided an effective tool to design devices that could control the electromagnetic wave with desired ray traces. However, the resulted material constitutive parameters for these devices are mostly inhomogeneous and anisotropic, which usually rely on large number of precisely defined sub-wavelength artificial structures, or metamaterials. In this paper, we show that by employing simple linear coordinate transformations, devices for antenna and invisibility cloak applications can be achieved with homogeneous birefringent dielectric media, which can be further constructed with multilayer of normal dielectrics, reducing the complexity of practical realization. Two examples, a planar retrodirective reflector and a ground plane invisibility cloak, have been successfully designed. The functionality has been validated through full-wave simulation, as well as experimental testing on the proto-type.