On the potential of sensor-enhanced active RFIDs

As the popularity of the passive RFID technology continue to surge, we see promising applications in its active counter-genre. There is however an inherently limited lifetime in any active RFID-based system because the active RFID tags operate on batteries. To hurdle through the energy limitation, we think the opportunities lie in the creative embedding and use of sensors with the active RFID tags. With a case study, referred to as the personal object alarm, we show the potential of embedding sensors to active RFID tags for optimal system lifetime and accuracy. In particular, from the range estimation sensor, we derive the relative distance and velocity of the active RFID tags on the user and object. In turn, out-of-proximity alert can be generated timely when the user´s personal object moves out of the predefined range. Our experiments show that with sensor-enhanced active RFID system lasts twice as long while the accuracy of the alert is improved by 47%, in comparison to a system without any embedded sensors.