Monopole Directional Antenna Bioinspired in Elliptical Leaf with Golden Ratio for WLAN and 4G Applications

Abstract In this work, it is proposed the development a monopole directional antenna, bioinspired in elliptical leaf, with aperture by golden ratio, for 4G band application. The shape antenna is generated by Gielis formula, built in FR4 substrate, with apertures calculated by golden ratio, for increasing the antenna perimeter, and to turner the resonance frequency. To compare the results of the bioinspired monopole on the elliptical sheet, a square-shaped monopole antenna was designed, simulated and measured, the structures were designed in the MATLAB program and the simulations were performed in the Ansys program. In the results compared between the square monopole and the bioinspired antenna in the elliptical sheet, it can be seen that the measured bioinspired antenna, compared to the square monopole, presented a bandwidth reduction of 77.27%, a more compact structure, with a reduction of 98%, covering the wireless local area network, and long-time evolution 4G at 2.5 GHz. The proposed technique uses a reflector on the ground plane, to change the parameters of the monopole planar antenna, of omnidirectional radiation pattern to a directional, maintaining the characteristics of the broadband, half-power beamwidth great than 100º, with high current density, and similar gain of a directional antenna. From the results, it has been observed that the elliptical leaf monopole antenna shows broadband characteristics, with a half-power beamwidth of 128 degrees, wideband, the bandwidth of 500 MHz, a gain of 6.28 dBi, a current density of 13.01 A/m², and circular polarization.