UHF RFID Sensor Tag Antenna Concept for Stable and Distance Independent Remote Monitoring

This paper presents a passive radio frequency identification (RFID) sensor transponder (tag) antenna concept that is based on the detection of defined tag signal patterns at the RFID reader. By detecting tag signal patterns rather than tag signal amplitudes or phases, as shown in previous work, the sensing can be made independent of the reader/tag distance. In addition, the tag with the custom-built antenna ensures a stable reader to tag and tag to reader communication. Initial verification measurements show that similar signal patterns can be detected for different tag positions, even in harsh multipath environments.