A Compact Ultra-wideband Single Element Planar Yagi Antenna

In this paper, we present a planar, single element ultra-wideband Yagi-Uda antenna. To feed the radiating element, a tapered microstrip balun is designed. The proposed antenna covers a wide frequency band of (1.2 GHz - 2.16 GHz), achieving a fractional bandwidth of 60%. The gain of the antenna lies above 5.2 dBi throughout the band, having a maximum gain of 7.23 dBi, within the smallest form factor (0.4λo x 0.54λo) reported so far for this frequency range. The antenna is fabricated on a low-cost FR4 substrate (1.5mm) and the measured results are in accordance with the simulations.