Affiliation:
1. Department of Electrical Engineering, Yazd University, Yazd 8915818411, Iran
Abstract
In this paper, a wideband flat lens antenna with low reflection and good performance is presented based on conformal transformation optics (CTO). Physical space optimization is applied to eliminate singular refractive index values. Furthermore, we employ the optical path rescaling method to enhance the sub-unity refractive indices and to reduce reflection. Therefore, an implementable all-dielectric isotropic medium is obtained. The final flat lens profile comprises six layers with a constant permittivity value in each layer. Simulation results of the three-dimensional structure indicate that the designed flat lens operates in a wide frequency bandwidth. The flat lens antenna has an S11 value of less than −15 dB in the frequency range of 13 to 30 GHz. The proposed lens was designed and simulated using COMSOL Multiphysics, and radiation performance results were validated using the CST Studio Suite. The simulated radiation pattern shows that the side lobe level is less than −16.5 dB in two simulation software programs, and the half-power beam width varies from 5.6° to 2.7° with increasing frequency. Moreover, the simulated antenna gain is about 28.3–35.5 dBi in the 13–30 GHz frequency range.
Subject
Electrical and Electronic Engineering,Mechanical Engineering,Control and Systems Engineering
Reference37 articles.
1. Werner, D.H., and Kwon, D.-H. (2014). Transformation Electromagnetics and Metamaterials, Springer.
2. Controlling electromagnetic fields;Pendry;Science,2006
3. Optical conformal mapping;Leonhardt;Science,2006
4. A full-parameter, broadband, homogeneous, and compact waveguide coupler designed with transformation optics;Yang;IEEE Antennas Wirel. Propag. Lett.,2015
5. Reflectionless compact nonmagnetic optical waveguide coupler designed based on transformation optics;Eskandari;Appl. Opt.,2017