High-Gain Antipodal Vivaldi Antenna Surrounded by Dielectric for Wideband Applications

In this communication, an antipodal Vivaldi antenna surrounded by dielectric (AVA-SD) is proposed for wideband applications such as microwave and millimeter-wave imaging, see-through walls, and radio astronomy. The main features of the proposed AVA-SD are wideband high gain, high front-to-back ratio, corrected the E-plane tilt of beam at wide bandwidth, narrow half-power beamwidth, and low sidelobe and cross-polarization levels. A prototype of the proposed AVA-SD is fabricated, and its performance is simulated and measured demonstrating operating frequency bandwidth from 5 to 50 GHz. The designed AVA-SD has overall size of $31.6\times110$ mm².