An Ultra-Wideband Miniaturized Dual-polarized Vivaldi Antenna

In this paper, an ultra-wideband (UWB) Vivaldi antenna with an impedance bandwidth of 800MHz-18.5GHz (23.1:1) is introduced. The two antennas are placed orthogonal to achieve 0° and 90° polarization. The antenna is fed by a fan-shaped microstrip feeder, several rectangular and triangular gaps and resistors are loaded on the radiation arms of the etched conical slot to effectively reduce the geometric size of the antenna and broaden the bandwidth. The size of the antenna is $70\text{mm}\times 45\text{mm} (0.187 \lambda_{0}\times 0.12 \lambda_{0},\quad \lambda_{0}$ is the maximum working wavelength). The VSWR parameters are less than 2:1, and the isolation of two ports is better than −23dB.