A Miniaturized Wideband Fractal Antenna Combining Sierpinski and Minkowski Fractals

In this article, a compact, wideband hybrid fractal antenna for wideband operation is designed. A combination of Sierpinski and Minkowski fractal geometry is applied to the patch to increase bandwidth and gain. The overall size of a radiator is $27 \times 37 \times 1.6$ mm$^{3}$ placed on a Roger RT Duroid substrate material. The Defective Ground Structure (DGS) method is applied with a rectangular-shaped slot on the ground plane to obtain the impedance characteristics. The radiator provides an impedance bandwidth of 76.3% covering the range from 3.6 GHz to 8.04 GHz. The maximum reflection coefficient of 29 dB has been attained at 7.2 GHz over the operational frequency range while the peak realized gain of 5.63 dBi has been achieved at 3.9 GHz. The radiating element exhibits a cross-polar difference of 44 dB with stable radiation characteristics making it suitable for wireless communication applications.