Chipless RFID tag with integrated resistive and capacitive sensors

A wireless sensor node based on a chipless RFID tag with integrated sensor element is presented. The chipless tag is multiresonator-based and encodes data as spectral signature. The sensor element is attached to a dedicated resonator of the chipless tag. Two types of sensor elements are used - resistive and capacitive. The resistive sensor output changes the Q factor of the spiral resonator effectively changing its insertion loss at the resonant frequency. The capacitive sensor output changes the spiral resonator´s resonant frequency. The wireless chipless sensor node can be used in various automated monitoring applications.