Nondestructive Evaluation of Fluid Characteristics using Compact Quarter-Mode SIW Resonator Sensor

Abstract

Novel compact quarter-mode (QM) substrate integrated waveguide (SIW) resonator sensor based on dielectric properties developed. The sensor works on the principle of material perturbation of the cavity resonator. It operates in the broader range of ISM frequency band to characterize various properties of pure liquids, their admixtures, and soluble solids in the solution. The sensor is excited by a 50-ohm microstrip line. A Teflon tube passes through one end of the sensor to hold the material under test (MUT). The variations in the dielectric constant of the material under test shift the resonant frequency. The simulation result shows adequate shifts in resonant frequency and dielectric constant dependent. Thus, this feature of resonate frequency shift assists in determining the component concentration, adulteration, or various properties depending on specific calibration. The findings suggest that the proposed sensor can be successfully applied to determine properties with high precision using a very small amount of fluid in a novel non-destructive approach.