Dual-polarized omnidirectional antennas with folded structures

Abstract

In this paper, we have presented two designs of dual-polarized antennas with omnidirectional radiation patterns in the azimuthal plane. For the first design, the vertical polarization is provided by a monopole with a co-planar waveguide feed; and the horizontal polarization is provided by a slot-coupled folded dipole structure. In order to reduce the antenna dimensions, the second design uses another method to achieve horizontal polarization with omnidirectional pattern. A slot-coupled cavity is utilized and integrated with the monopole, which is also used for vertical polarization. For both designs, the simulated bandwidths cover the desired band of 2.4–2.48 GHz with S11(S22) 0 ×0.24λ 0 ×0.07λ 0 , λ 0 is the free-space wavelength at 2.44 GHz).