An EIT-Based Compact Microwave Sensor With Double Sensing Functions

Microwave sensors, which utilize the peculiarity of microwave to detect conditions and status of an object, have been widely used in electromechanical conversion, biochemical sensing, and environmental monitoring. In this paper, the concept of electromagnetically induced transparency (EIT) is adopted in the sensor design, and a compact microwave sensor is proposed with double sensing functions and works well under different electromagnetic conditions. High sensitivities of 13.709 mm/refract index unit for the EIT-window response and 10.6 MHz/fF for the dark mode operation are obtained, respectively. The proposed sensor is simulated, fabricated, and tested. Good agreement is obtained between the simulation and measurement results.