Fractal Sectoral Monopole Antenna for UWB Band Applications

Abstract

This paper proposes a fractal monopole antenna based on a sectoral-shaped patch. To improve thegain of the proposed antenna over a larger bandwidth, the matching was enhanced by attaching two rectangular stubs to the feeding line. The antenna, which is built on an FR4 epoxy substrate with εr =4.3 and a loss tangent of 0.018 has a compact size of 28 mm×31 mm×1.6 mm. The antenna covers the UWB range and extends to about the 22 GHz frequency, as well as offers omnidirectional radiation patterns. The optimized configuration was fabricated and tested. The impedance bandwidth of the proposed antenna is about 155% with a reflection coefficient better than −10 dB and has a maximum gain of nearly 4 dBi with a relatively stable omnidirectional radiation pattern.