Investigation of Frequencies Characteristics of Modified Waveguide Aperture by Wire Media

Abstract

The paper is devoted to the investigation of radiation frequencies characteristics of a modified waveguide aperture by wire media (WM). Such construction allows radiating weak electromagnetic (EM) waves-their frequencies are non-corresponding to the resonant ones of the modified radiator. It is possible due to the unusual properties of metamaterials, namely the negative value of permittivity of WM. The study of the simulation shows that the changing of value of wires radius and at the same time the value of filling factor impacts on the radiation frequency. Therefore, the increase of the filling factor leads to the increase of the resonance frequency. The radiation is narrowband with S 11-parameter less than −20 dB. The experimental investigation shows that the decrease of the value of lattice period allows increase of the width of radiation frequency range from 30-40 MHz up to approximately 80 MHz at the level of 0.3 (≈ −10 dB). At the same time, the increase of wires' radius values leads to the increase of the value of resonant frequency. Finally, the experimental study demonstrates that the value of overlap between waveguide port (source of EM waves) and WM sample negligibly impacts on the resonance frequency values and operational range for D/L = 0...0.3.