Hemispherical Dielectric Resonator Antenna Based on Apollonian Gasket of Circles—A Fractal Approach

Abstract

A novel, compact hemispherical dielectric resonator antenna based on Apollonian Gasket of circles is proposed. The Apollonian Gasket is a fractal generated from triplets of circles, where each circle is a tangent to the other two. The dielectric material used is Rogers TMM 10, which is a ceramic thermoset polymer composite material having a dielectric constant of ε <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">r</sub> = 9.2. The fractal geometry offers a wide impedance bandwidth of around 1.68 GHz (47%) for S <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">11</sub> <; -10 dB at a resonant frequency of 3.6 GHz. Experiments have been conducted up to the third iteration of fractal. Two modes have also been investigated which show presence of both like and like modes. For like mode, the antenna radiates with a gain of around 6.5 dBi whereas for like mode, the antenna radiates in the broadside direction with a high gain of 8.5 dBi.