Ring Resonator with single gap for Measurement of Dielectric Constants of Materials

Abstract: The significance of calculating and measuring dielectric constant is important for all the fields of study and research from biological science to electronics and telecommunication. It gives a better characterization of the material and helps to design the accurate system, and aside these two functions, it has numerous uses. Owing to its huge expediency, various measurement methods of dielectric constant of materials have been developed by scientists and engineers over the years. Each method has its limitations which affect the accuracy of the measurement; these limitations range from frequency, temperature, measurement environment to material under test. In this research work, we measured the resonant frequency of the ring resonator using different materials and then we measured the dielectric constant of different materials by using that resonant frequency. We discussed different common methods of measuring dielectric constant and the most accurate one, the resonant method, was chosen and driven upon .The project was done by making a mathematical analysis for the geometry of the ring resonator, wrote MATLAB script for the measurement of the resonant frequency, later designed and simulated in HFSS to obtain results which would be comparable to ones obtained in laboratory measurements. The ring was fabricated and taken to the laboratory for measurement of the resonant frequency for measuring dielectric constant of different materials; two monopole antennae were connected to the two ports of a vector network analyzer with one antenna serving as the transmitter and the other serving as the receiver. When we used the MUT in the gap of the ring resonator we saw frequency shift in the resonant frequency and we noted that resonant frequency. The resonant frequencies obtained were compared with the geometric parameters of the ring resonator and that of the MUT in an equation written into MATLAB script; this equation was used to extract the dielectric constant of the MUT and then we calculated the dielectric constant by using the resonant frequency of the MUT.