Compact Embedded Dual-Element Rectangular Dielectric Resonator Antenna Combining Sierpinski and Minkowski Fractals

Abstract

In this paper, a novel embedded dual-element rectangular dielectric resonator antenna (RDRA) combining Sierpinski and Minkowski fractals is proposed to reduce the size and for wideband applications. To enhance the impedance bandwidth, a DR <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">1</sub> with dielectric material Rogers RT6010 (ε <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">r1</sub> = 10.2) is embedded concentrically inside the DR <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> . DR <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> is a rectangular ring with dielectric material FR-4 (ε <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">r2</sub> = 4.3). The proposed antenna offers a wide impedance bandwidth of around 3.52 GHz (66%) 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 3.85 GHz. Experiments have been conducted up to the second iteration of fractal with various indentation factors. Two modes have also been investigated that show presence of both TE <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">11δ</sub> <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">Z</sup> (0 <; δ ≤ 1) like and TE <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">11δ</sub> <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">Z</sup> (0 <; δ ≤ 1) like modes. The peak gain of proposed antenna is 6.74 dBi at 6.25 GHz. The measured gain is above 5.13 dBi in the frequency range from 3.5 to 7.02 GHz (impedance bandwidth) of operation.