Design of microwave ENZ sensor for contamination detection in liquids using SIW technology

A novel planar epsilon-near-zero (ENZ) tunnel sensor is designed using the surface integrated waveguide (SIW) technology for detection of contamination in various liquid solutions. The contamination is detected in terms of the volumetric percentage by measuring the change in the dielectric properties of reference and adulterated solutions. The method is based on the cavity perturbation technique in which the tunneling electric field gets perturbed by the sample inclusion. An accurate sensitivity analysis shows the advantage of the proposed ENZ sensor over the conventional SIW cavity for accurate measurement of liquid contamination. Various types of adulterated liquid solutions are tested with the help of the specially designed sample holder, and the results are found to in good agreement with the theoretical values.