Chipless RFID temperature threshold sensor and detection method

Abstract

We study NaCl-water solutions as the temperature sensitive material for chipless RFID-based temperature threshold sensing, detecting and storing the event if a given threshold temperature is surpassed. Different solution concentrations are evaluated simultaneously with a sensor that can detect multiple temperature thresholds. A new method for background interference subtraction is presented, which relies on previous measurements to perform a dynamic background subtraction allowing the detection of sensor changes in situations where the background response varies with time.