Design of multiband fractal antenna loaded with parasitic elements for gain enhancement

摘要

In this article, a multiband fractal antenna loaded with parasitic elements for gain enhancement is reported. The proposed radiator has a nested hexagonal loop with an opening at the top. The three hexagonal open loops with a small hexagonal radiator at the center, is fed with a microstrip line. The proposed design composed of parasitic elements to enhance the gain of the antenna. By loading two parasitic elements in the opening of the antenna, gain performance improved by 2 dB at each resonant frequency which are 2.07, 3.73, and 4.96 GHz. The proposed antenna is covering an impedance matching less than −10 dB in the frequency bands of (1.96-2.22) GHz, (3.51-3.91) GHz, and (4.78-5.26) GHz which are supported for LTE, 5G and WLAN applications. An omnidirectional radiation pattern in both E-plane and H-plane at all three resonant frequencies is observed. The overall size of the fabricated antenna has a dimension of 37 mm × 28 mm × 1.6 mm, which is fabricated on FR-4 laminate. A very high correlation is observed between the simulated and measured characteristics.