Wideband Monopole-Like Cup Dielectric Resonator Antenna With Coil Feeding Structure

A wideband cup dielectric resonator antenna (CDRA) with a monopole-like mode is presented. A new coil feeding structure is used, creating an equivalent magnetic current loop above the ground plane, exciting the CDRA
$\textrm {TM}_{01 \delta } $
mode and an equivalent electric dipole at the adjacent frequency band. Thus, a broad bandwidth is achieved from two adjacent resonances. A CDRA with
$0.25\lambda _{0} $
diameter and
$0.23\lambda _{0} $
height (
$\lambda _{0} $
is the center frequency free-space wavelength) is fabricated and measured. About 29% of −10 dB matching bandwidth (2.98–4.00 GHz) is achieved. The structure has a low cross-polarization level and stable radiation patterns within the entire operating bandwidth.