Wideband cavity-backed bowtie antennas

Abstract

For wideband antennas with unidirectional patterns, it is a troublesome problem to stabilize the antenna patterns across a very large frequency band. In our work, cavity-backed structures are utilized with bowtie exciters. The patterns of the proposed cavity-backed triangular bowtie antenna (TBA) with rounded corners can be stabilized within a 92% frequency band without side lobes, by placing a circular ring between the ground plane of the cavity and the TBA. Similar performances can also be achieved by a dual-folded TBA backed by the same cavity. Much wider available bandwidth can be achieved by employing complex cavity.