Phase-of-arrival-based localization of passive UHF RFID tags

This paper introduces a novel 2D localization system for passive UHF RFID tags based on phase-of-arrival evaluation of the backscattered tag signal received by several antennas. To improve localization accuracy and reduce disturbances caused by multipath propagation, we employ a frequency-stepped continuous waveform approach. To achieve proof of concept, a local position measurement system demonstrator comprising an RFID reader, passive EPC Gen 2 RFID tags, several receivers, baseband hardware, and signal processing was used for measurements in an anechoic chamber.