Application of Micro-Genetic Algorithm to the Design of Matched High Gain Patch Antenna with Zero-Refractive-Index Metamaterial Lens

Abstract

This paper presents a method for the computer aided design of high gain patch antenna with Zero-Refractive-Index (ZRI) metamaterials using Micro-Genetic Algorithm (MGA) and finite-difference time-domain (FDTD). The ZRI metamaterials, which is composed of metallic grids with periodic square lattice and slices of medium, is placed in front of the conventional patch antenna as a lens. The design progress and results are presented and discussed. A prototype of such a designed antenna has been fabricated and tested. The measured radiation patterns and return loss of the antenna are compared with the computed results, and a good agreement is observed. The ZRI lens can maintain 10 dBi maximum gain enhancement compared to the conventional patch antenna from 11.5 GHz to 12.5 GHz. The measured results show that the patch antenna with the ZRI lens has an impedance bandwidth in the range from 11.70 GHz to 12.56 GHz for S ₁₁ < −10 dB.