Determination of dielectric constant and loss-tangent of substrate sheet using microstrip patch resonator

This paper presents a new microstrip rectangular patch resonator based method to determine the dielectric constant and the loss tangent of a dielectric material in sheet form. Using an improved form of the cavity model, called the modified Wolff model (MWM), the present method extracts these two parameters from the measured resonance frequency and Q-factor. The MWM takes care of all kind of losses in the patch, resulting in accurate determination of the dielectric constant and loss tangent of the substrate.