Complex Permittivity Measurement for Thin Dielectric Rods with High Permittivity Using a 50 GHz Band TM010 Mode Cavity

Realization of a sustainable smart society requires the rapid development of various millimeter wave devices. Applying an FDM type 3D printer is one of a solution for fast and low-cost microwave and millimeter wave circuit manufacturing. However, complex permittivity of 3D printer materials has not been enough reported. We have been proposed an accurate measurement method for a thin dielectric rod with a low permittivity using a 50 GHz band TM010 mode cavity. In this paper, we propose a millimeter wave measurement method for low loss dielectric thin rods with a high dielectric constant using the 50 GHz band TM010 mode cavity with a small insertion hole. Two types of 3D printer filament with high permittivity are used as thin rod samples. As a result, the proposed method is revealed complex permittivity for the filament rod and can be useful to measure a thin dielectric rod with a high permittivity at a 50 GHz band.