A 3D-Printable High-Permittivity Ceramic Material for Lightweight Dielectric Resonator Antennas

This paper presents a new 3D-printable titanium oxide (TiO2) based composite, compatible to Fused Deposition Modeling (FDM) technique, for microwave applications. After sintering, a dielectric constant of 80.7 +/- 2.2 and a loss tangent of <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$4.610^{-3}+/-0.2.10^{-3}$</tex> were measured on the 3D filament at 5 GHz. The additive manufacturing of this material with sub-wavelength structuration enables the generation of high permittivity effective media with considerably reduced densities. In this paper, a frequency analysis of the effective permittivity is given for gyroid unit-cells with three low filling ratios of 20, 30 and 40% using the Plane Wave Expansion Method (PWEM). Finally, a very lightweight antenna of 15g operating in S band is presented. Although the sintering procedure still needs some optimization to further enhance the results, a mass reduction close to 3.3 was obtained with the antenna in TiO2 compared to its counterpart in zirconia.