A Design of Simple Vertically Polarized Vivaldi-Based Omnidirectional Antenna for X-Band

A simple Vivaldi-based omnidirectional antenna for X-band is presented. By placing two Vivaldi antennas in opposite directions, a simple microstrip power divider can excite two antennas simultaneously. In addition, ellipse slot restrains the upward radiated energy and reduces the side lobe. Using different exponential ratios of both sides of tapered radiating slot, metal patch loaded and different sized circle slots guarantee that the direction of maximum radiation is horizontal. The structure of proposed antenna is simple, small and easy to fabricated. The prototype antenna is manufactured and measured. And measured results show good antenna performance and agree well with the simulation.