Chipless RFID Multisensor for Temperature Sensing and Crack Monitoring in an IoT Environment

Nowadays, structural health monitoring and thermal contemplation of remote places are of serious significance. In this scenario, chipless radio frequency identification (RFID) sensors are the vital enablers to monitor remote circumstances in the low-cost pervasive network. This letter presents a compact 7-bit chipless RFID multiparameter sensor designed on smart Rogers RT/Duroid 6010.2LM material. The material alters its dielectric properties concerning temperature fluctuations. Six inverted "U" and "L" shaped resonators are designed with specific length and width to resonate within the desired frequency band of 2-8 GHz. A circular microstrip patch antenna is used for the characterization of the crack. The measurements are performed outside the anechoic chamber in an electromagnetically quiet environment. The realized novel smart sensor can be attached to monitor any crack in the metal surface, where temperature monitoring is also crucial. The proposed state-of-the-art robust multisensor is suitable for long-term applications.