Dielectric measurement using a planar ring sensor for low-loss powder form materials

Abstract

This paper uses planar ring sensor for dielectric measurements of low-loss powder materials by applying conversion of measured reflection coefficient to relative dielectric constant via a lumped-element model. The ring sensor has been fabricated using 1.58mm thickness of FR4 substrate and designed to operate at a frequency range between 1 GHz to 3 GHz at room temperature. This sensor was tested on free space and various types of powder. In this study, the predicted dielectric constant is in general agreement with the results obtained using a commercial dielectric probe.