3D Printed Wideband Dielectric Rod Antenna with Surface Wave Manipulation at a Low Cost

A rectangular dielectric rod antenna (RDRA) 3D printed using a liquid crystal display resin method, aiming at the improvement of the radiation pattern for a narrow beamwidth, low sidelobe level, and wide bandwidth is presented. To realize both good radiation performance and fabrication simplicity, aluminum oxide
$\boldsymbol{(\mathrm{A}1_{2}\mathrm{O}_{3})}$
powder and air holes are used to modify the permittivity of the commercial resin. In addition, a horizontal air-cavity penetrating the middle of the dielectric rod is designed to eliminate higher-order surface wave modes. The antenna is 3.97
$\boldsymbol{\lambda_{0}}$
in length and holds an identical orthogonal cross-section of 0.48
$\boldsymbol{\lambda_{0}\times 0.35}$
λ0. Measurement results show that the proposed RDRA exhibits a gain of 12.7 dBi and
$\boldsymbol{32^{\circ}}$
half-power beamwidth (HPBW) in both E- and H-plane at 24 GHz.