Top loaded TM01δ Mode Cylindrical Dielectric Resonator for Complex Permittivity Characterization of Liquids

This paper reports on a technique of using a very high quality factor cylindrical dielectric resonator operating in TM01δ mode to characterize liquids available in trace quantities. The proposed measurement technique is based on the resonant perturbation theory and the resonator is used as a sensor to determine complex permittivity of solvents at 10.5 GHz. Owing to a very high unloaded quality factor of about 5000 the proposed sensor can characterize low to medium loss materials with high accuracy. Small quantities of isopropanol and ethanol have been characterized to compute their solution ratio when mixed with different quantities of distilled water. Low cost and versatility of the proposed structure make it a prime choice for pharmaceutical industry where high standards of purity need to be ensured.

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