A novel slotted dumbbell-shaped dielectric resonator antenna with enhanced bandwidth for C-band and 5G sub-6 GHz applications

This manuscript presents a novel aperture-coupled fed slotted dumbbell-shaped (SDS) dielectric resonator antenna (DRA) with enhanced bandwidth for 5G sub-6 GHz, short-range wireless communications, and C-band applications. The DRA is excited by HEM11 delta mode. The proposed SDS-DRA is designed by assembling the four frustums of conical DRAs with the base and apex of one on top of another. The measured operating frequency of SDS-DRA is from 3.5 GHz to 9.6 GHz (impedance bandwidth of 93.1 %). The SDS-DRA shows a peak gain of 9.7 dBi in the operational frequency range, with an average peak gain of 6.02 dBi. The antenna's average radiation efficiency is found to be 84.6 %. The proposed SDS-DRA produces omnidirectional-like radiation patterns with significantly low cross-polarization in the broadside direction. The size (l x w x h) of the proposed SDS-DRA is 1.55 lambda g x 1.55 lambda g x 0.67 lambda g where, lambda g is the guided wavelength in mm at 3.5 GHz for effective permittivity (epsilon eff ), 7.1. To validate the simulation results, the proposed antenna structure is built, and its performance is measured. The findings of simulation and measurement results are found to be quite congruent.