Development of a low cost printable humidity sensor for chipless RFID technology

In this paper, a low cost, printable chipless RFID humidity sensor is presented. The RFID sensor is based on planar stepped impedance resonator (SIR) structure. Humidity sensing mechanism is incorporated using dielectric change of commercially available Kapton HN polyamide. A prototype sensor is designed, fabricated and tested with standard experimental measurements. Results verify that the humidity sensitivity can be measured for both frequency and minimum power level difference. The proposed chipless RFID sensor platform has potential of integrating multiple sensing parameters for ubiquitous environment monitoring.