Device tracking using Ultrasonic Sensor By passive RFID tags

Contrivance-free object tracking provides a promising solution for many localization and tracking systems to monitor non-cooperative objects, such as intruders, which do not carry any transceiver. However, subsisting contrivance-free solutions mainly use special sensors or active RFID tags, which are much more extravagant compared to passive tags. In this paper, we propose novel kineticism detection and tracking method utilizing passive RFID tags, denominated Twins. The method leverages an incipiently observed phenomenon called critical state caused by interference among passive tags. We contribute to both theory and practice of this phenomenon by presenting an incipient interference model that precisely expounds it and utilizing extensive experiments to validate it. We design a practical Twins predicated intrusion detection system and implement an authentic prototype by commercial off-the-shelf RFID reader and tags. Experimental results show that Twins is efficacious in detecting the moving object, with very low location errors of 0.75 m in average (with a deployment spacing of 0.6 m).