A Low-profile Wideband Dual-Polarized Omnidirectional Antenna for 2G/3G/LTE/Sub-6G Applications

A low-profile wideband dual-polarized omnidirectional antenna is designed for 2G/3G/LTE/sub-6G technologies. The dual-polarized antenna consists of two parts, i.e., a vertically polarized tapered gradient monopole and a horizontally polarized connected Vivaldi antenna array. The horizontal polarization (HP) element is designed as the metal ground of the vertical polarization (VP) element to avoid match deterioration when the HP element is positioned closely to the metal ground of the VP element. Thus, the dual-polarized antenna realizes an extremely low profile of 0.07 λ
min
(λ
min
is the wavelength at the minimum frequency in the operational band). The designed antenna achieves an overlapping bandwidth of 1.7-8 GHz (130%) and an isolation higher than 20dB within the band. In the azimuth plane the simulated gain changes less than 3dB for both VP and HP elements within the operating band.