Broadband millimeter‐wave composite cavity backed antenna with bowtie exciter

Abstract

A wideband cavity-backed antenna is proposed in this article. For performance improvement, an elliptical composite cavity is adopted and it is excited by a rounded bowtie dipole through a transition from a microstrip line to a parallel strip line. To reduce the fabrication errors, the antenna aperture is designed to be over 0.84 wavelength at the lowest operating frequency, and the exciter is built on a substrate along with the transition by the printed circuit board (PCB) techniques. Measurements show that the antenna can be operated in a frequency band of 30.6-70 GHz for SWR 2 and stable radiation patterns.