Miniaturized Self-powered UHF RFID Tag-based Sensor

This paper presents a low-cost self-powered UHF RFID tag-based sensor. The proposed tag-based sensor comprise a miniaturized dual-feed loop tag antenna incorporated with multiple RFID chips and a resistive sensor for utilizing reference and sensor nodes. One RFID chip is integrated in the reference node transmitting in the sensing process, and another one with integrated sensor (sensor node) transmits a signal impacted by the sensed data. By measuring the power ratio of the required minimum power transmitted by the reader to wake-up the RFID chips in both the reference and sensor nodes, the reader then can extract the sensed data i.e. temperature. The miniaturized RFID tag-based sensor is fabricated and experimentally evaluated. The measured results demonstrate that the developed miniaturized dual-feed tag-based sensor can be integrated with resistive sensor for low-cost wireless sensor nodes.