Cylindrical electromagnetic transparent device with only axial material parameter spatially variant
Electromagnetic transparent device plays an important role in antenna protection. In this article, we design a simplified cylindrical transparent device with only axial material parameter spatially variant based on coordinate transformation method. The general expressions of material parameters are derived, and then, the performance of the transparent device is simulated based on the full wave simulations. The advantages of the transparent device are that transverse material parameters are constants, and both axial and transverse parameters are nonsingular and positive, which makes it easier to realize with two-dimensional metamaterials. Besides, the effects of loss and perturbations of parameters on the performance of the device are also investigated. Finally, potential application of the transparent device in antenna protection is numerically demonstrated. This work provides a feasible way for the fabrication of the metamaterial-assisted transparent device.  2012 Wiley Periodicals, Inc. Int J RF and Microwave CAE 22:522529, 2012.
transparent device antenna protection coordinate transformation metamaterials