A Low-Profile Filtering Dielectric Resonator Antenna Based on Metal Bridge Loading

In this letter, a low-profile filtering dielectric resonator antenna (DRA) is presented. A hybrid DR consisting of three DRs with two different dielectric constants and dimensions is adopted in this design. Radiation nulls are generated by loading a shorting pin at the end of the microstrip line and two metal bridges between the three DRs. Then, a new resonant mode can be excited near the two resonant modes by adding a transverse stub in the feed line. To improve impedance matching and out-of-band suppression, metal posts and L-shaped and curved cross-shaped stubs with shorting pins are introduced into the proposed filtering DRA (FDRA). For demonstration, an 11.05 GHz prototype is fabricated and measured. The measurements are in good agreement with the simulated results, and the profile of the prototype is only 0.09
${{\lambda }}_0$
.