High Q Ba(Zn1/3Ta2/3)O3 microwave resonator in a closed cavity for sensor applications

Abstract

Microwave dielectric resonator having a high Q-factor results in high sensitivity and it can be used as a sensing element in wireless passive sensor systems. In the present work, we demonstrated high Q resonator enclosed in a metallic cavity which is highly sensitive to resonance frequency and quality factor change arising from small test samples kept on the surface of the resonator. The measurements are made at the resonance frequency of TE10δ mode. The Ba(Zn1/3Ta2/3)O3 resonators prepared by solid state reaction method exhibits high Q value of >12,500. The experimental studies have been conducted on different type of rice grains cut to uniform size and shape to explore the response of resonance frequency and Quality factor. The change in effective dielectric constant and loss tangent of resonator with test samples were measured. Our work should provide a general guidance in development of high Q dielectric resonators for sensor applications.