A Printed Beam-Shifting Slab Designed Using Tensor Transmission-Line Metamaterials

We present the design and implementation of a beam-shifting slab (a transformation electromagnetics device) using tensor transmission-line metamaterials. A beam-shifting slab is an anisotropic, homogeneous and reflectionless slab which laterally displaces the electromagnetic field transmitted through it. The experimental beam-shifting slab consists of printed metamaterial unit cells exhibiting anisotropic effective material parameters, while the surrounding medium consists of printed isotropic unit cells. The measured and simulated field patterns within the beam-shifting slab and the surrounding media are compared and show excellent agreement. Simulation and experimental results demonstrate that radiation from a cylindrical source is shifted upward by 5.28 unit cells due to the presence of the beam-shifting slab. Furthermore, the wide-band frequency response of the slab is experimentally studied. The reported experimental results verify the theory behind tensor transmission-line metamaterials and demonstrate their utility in the design of transformation electromagnetics devices at microwave frequencies.