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.