Dual-Mode Cylindrical DRA: Simplified Design With Improved Radiation and Bandwidth

A dual-mode dual-band cylindrical dielectric resonator antenna bearing a unique combination of improved radiation and input impedance characteristics has been reported in this letter. An innovative concept of twin aperture with a single microstrip feed has been successfully explored. It demonstrates uniform excitation of the broadside radiating HEM
_11δ
and HEM
_11Δ
with 1<Δ<2(Δ≃1+
δ
) modes operating at S- and C-bands. Experimental studies with a set of prototypes ensure 10% matching bandwidth at each resonance with 6.3 and 9 dBi peak gains, respectively. Considerably enhanced co-polar to cross-polar isolation at both operating frequencies is the additional attractive feature. Apart from the structural simplicity, such an elegant combination of the operating bandwidth with both co-polar and cross-polar radiation characteristics appears much improved compared to its earlier dual-band variants.