A 3D-Printed Wideband Multilayered Cylindrical Dielectric Resonator Antenna With Air Layers

A wideband multilayered cylindrical dielectric resonator antenna (CDRA) using 3D-printing technology is investigated. It includes three cylindrical dielectric rings with decreasing effective dielectric constants, interspersed with two air layers. This multilayered DRA is combined on a cylindrical insert layer with a low dielectric constant to get better impedance matching. To facilitate the 3D-printing, a simple hollow cube unit cell is utilized to reconstruct this multilayered DR. A coaxial probe is used to excite this DRA with multiple TM modes. By merging these modes, a wide measured -10 dB impedance bandwidth of 65.7% (3.56-7.04 GHz) can be obtained, with measured realized gain varying within 2.3 dB across the passband.