A Dual-Polarized Vivaldi Antenna for Tree Radar Applications

A dual-polarized Vivaldi antenna with a compact size and high gain performance is designed for tree radar applications. The antenna consists of four Vivaldi elements, two of which are orthogonal to the remaining two. Each pair of two elements works together in an array configuration to form a single polarization, while two pairs form a dual polarization with a shared aperture. To increase the radiation performance, planar directors and edge slots are introduced in the design of a single Vivaldi element, and a reflector is placed behind the Vivaldi elements. The simulation results show that the designed antenna achieves a high gain ranging from 5.5 to 15.6 dBi, while its cross-polarization discrimination is larger than 30 dB, demonstrating its high purity for each polarization.