This paper describes a nondestructive measurement method for complex permittivity of dielectric plates at 2 GHz, using a cylindrical cavity resonator. The resonator is divided into two parts at the center. Two dielectric plates are symmetrically loaded around the center of the cavity. These plates have high permittivity of 45. A dielectric plate specimen is clamped with these halves. The values of relative permittivity ε and loss tangent tanδ of the specimen are obtained from the resonant frequency and unloaded Q-value of TE011 mode. Measured results of various materials are compared with those values obtained at 3 and 10 GHz by other cavity resonator method. An edge effect is taken into account by a reference method, using measurement data of a sapphire plate. The errors of the present method are smaller than 1% and 2-310-5 for ε and tanδ, respectively.

This paper describes a nondestructive measurement method for complex permittivity of dielectric material at pseudo microwave frequencies. The resonator used in this study has a cylindrical cavity filled with a sapphire material of a well known complex permittivity. The resonator is divided into two parts at the center. A dielectric substrate specimen is clamped with these halves. Relative permittivity εand loss tangent tan δ of the specimen are obtained at 3 GHz using the TE011 resonance mode. The accuracy of the present method is evaluated through the comparison of the measured values by the new method with those at around 10 GHz by the conventional empty cavity resonator method. The errors of measurements are smaller than 1% and 1105 for εand tan δ, respectively.