A Metamaterial-Inspired Dual-Band High-Sensitivity Microwave Sensor Based on Multiple Split Ring Resonators for Sensing Applications

This paper introduces the design, manufacture, and evaluation of a compact metamaterial-inspired sensor, aiming at detecting dielectric properties of small liquids in a microwave measurement system. The proposed sensor is based on a microwave-coupled multiple split ring resonators (MSRR). The sensing principle is based on field perturbation theory. Then the sensor's resonance characteristics will change when the sensor is loaded with the materials under test (MUT). We have demonstrated that the sensor has a very high sensitivity to sensing the dielectric variations of its surroundings. When the resonance occurs, the strongest electric field intensity of the sensor is better than 105 V/m. The proposed sensor is simulated and optimized using ANSYS high frequency structure simulator (HFSS) to ensure its operating frequency is near 3 GHz and 4.5 GHz. Measurement results agree well with the simulation results. Some experiments show that this sensor can detect the dielectric property of liquids with very small volumes (similar to 12.56 mm(3)). (C) 2019 The Electrochemical Society.