Wideband Millimetre-Wave Dielectric Resonator Antenna Fed by a Wide Aperture

Abstract

This work presents a millimetre-wave (mmW) dielectric resonator antenna (DRA) excited by a wide aperture for bandwidth enhancement on the DRA and its array. The proposed antenna consists of a rectangular DRA top loaded with a metallic patch to produce two DRA modes on the radiator. The wide aperture is etched on the top metallic surface of a substrate-integrated waveguide (SIW) for contributing a slot mode and exciting the DRA. The proposed aperture is relatively wider than the conventional means of aperture-coupled DRAs, its size is almost identical to the base area of the DRA. An intensive parametric study proved using a wide aperture for excitation can lower the reactance of the higher-order mode of the DRA and thus expand the bandwidth. In addition, a 16-element DRA array with a 1-to-8 full corporate feeding network is introduced. A prototype of the array was fabricated and measured. The array exhibits a wide impedance bandwidth of 35.5% from 25.5 to 36.5 GHz for the reflection coefficient ≤ -10 dB and the maximum gain of 18.5 dBi. Throughout the operating bandwidth, stable broadside radiation patterns can be observed. A good agreement between the measured and simulated results can be obtained, which confirms these proposed designs found potential applications in the mmW wireless communication systems.