Microstrip line‐fed fractal antenna with a high fidelity factor for UWB imaging applications

A printed microstrip line-fed fractal antenna is presented with a high fidelity factor for UWB applications. The antenna structure of electrical dimension 0.24 λ × 0.33 λ at lower frequency 3.1 GHz is made of a fractal patch, a slotted partial ground plane, and a microstrip feed, which is fabricated on FR4 material of low cost and dielectric. Measured results demonstrates that the fractal antenna achieves fractional bandwidth of 117.88% covering the frequency range from 3.1 GHz to more than 12 GHz with a maximum gain 3.54 dBi at 6.25 GHz. An acceptable analogy is observed between measured and simulation results. The high fidelity factor, sharply surface current distribution, time domain performances, acceptable gain, and nearly omnidirectional radiation characteristic have validated the appropriateness of this proposed fractal antenna for UWB and microwave imaging applications. © 2015 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:2580–2585, 2015