Microstrip Ultra-wideband Omnidirectional Vertically Polarized Antenna

A microstrip ultra-wideband omnidirectional vertical polarization antenna is designed. The antenna consists of an elliptical ground, a metal fixator, a radome, a feed structure, and a radiator. Specifically, the relative dielectric constant of the antenna substrate is 4.4, the antenna substrate is fixed by a metal fixator and perpendicular to the metal base, On one side of the substrate, a slot is etched on the microstrip patch. On the opposite side of the substrate, a U-shaped microstrip structure is designed to feed the slot. A radome is added to the outside of the antenna, and the profile of the radome in the horizontal plane is elliptical. The overall streamlined structure of the radome makes the antenna applicable to aircraft, unmanned aerial vehicles, and other carriers. The size of the radome is 142.00 mm × 62 mm × 146.33 mm. The simulation results show that when the reflection coefficient is less than −10 dB, the bandwidth coverage is 0.69 ∼ 1.31 GHz. The relative bandwidth reaches 47.3%. The gain is relatively flat and greater than 3 dBi in the passband. The thickness of the substrate is only 1.6 mm. The antenna size is 0.270λ
min
× 0.246λ
min
, where λ
min
is the free-space wavelength at the lowest frequency of the operating band. The antenna has a low manufacturing cost and is suitable for a variety of broadband applications.