A Planar Cavity Backed Slot Antenna Array For Ultra-wideband Monopulse Radars

In this thesis, a wideband cavity backed slot antenna is designed for automotive-borne monopulse radar applications. A rectangular slot is used to realize broad bandwidth; the slot is backed by a cavity and vertical walls of the cavity are implemented by discrete vias; and the slot is fed by an inverted microstrip line. The antenna in this letter is compact, robust, fully planar, and easy to integrate. A two-element array is fabricated and tested. Measured input impedance is matched to 50-ohm within band [2.61 GHz, 3.44 GHz] (27.5% bandwidth); and monopulse beam-scanning is successfully demonstrated.