A Horizontally Polarized Omnidirectional Antenna Array with Side-Lobe Suppression

A broadband horizontal polarized omnidirectional antenna array with low side-lobe is presented. The proposed array consists of four wideband omnidirectional antenna elements and an uneven power divider. The antenna element consists of four pairs of arc dipole and a balun. Simultaneously, the slots placed at the edge of the arc dipole further broaden the impendence bandwidth. With PSO (particle swarm optimization) optimizing the different amplitudes of each element and element spacing, the side-lobe suppression is obtained. The simulation results show that the proposed antenna element and antenna array can achieve a bandwidth of 1.68-2.37 GHz and 1.72-2.37 GHz (S11<;-10dB), respectively. With an omnidirectional radiation pattern in H- plane and a low side-lobe of -19dB in E-plane, the antenna array has peak gains ranging from 5.75 to 7.2 dBi.