A Frequency Band Enhancement of Miniaturized Rectangular Waveguide Antenna Using Infinity Shaped Split Ring Resonator

this paper presents a miniaturized open-ended rectangular waveguide antenna radiating below the cut-off frequency of the waveguide with a large bandwidth. Waveguide miniaturization is achieved by periodically loading the antenna with electromagnetic metamaterials consisting of infinity shaped resonators. The metamaterial cell is designed to have a high effective dielectric permittivity in the frequency region below the cutoff frequency of the waveguide. HFSS software was used to obtain the transmission characteristics of the structure, which are then used to retrieve the effective material properties. Furthermore, the effective dielectric permittivity of the metamaterial cell exhibited a resonance around 5.2GHz. The waveguide antenna was designed and simulated using HFSS software. Comparing previous work of miniaturization of waveguides, a higher miniaturization ratio with a bandwidth about 1GHz and good matching is obtained. Keywords— metamaterial, infinity-shape cell, high permittivity, waveguide antenna, miniaturization, large bandwidth.