Measurements of Complex Permittivity Using Dielectric Resonator at 60 GHz

In order to investigate the characteristic of single crystal and polycrystalline ceramics at millimeter-wave frequencies, a method for measuring low-loss dielectric materials has been developed. Using a dielectric rod resonator excited by a dielectric waveguide, effective conductivity of conducting plates for short circuiting the resonator is determined. The complex permittivity of the dielectric rod is determined by the resonant frequency and unloaded quality factor of the TE_0ml-mode resonator. Then the complex permittivities of single crystal sapphire, polycrystalline ceramics, and cordierite have been obtained at 60 GHz. Finally, for all the specimens measured in this paper, the proposed method is seen to provide much better accuracy for values.