Hybrid Inertial Microwave Reflectometry for mm-Scale Tracking in RFID Systems

This paper proposes a new fine-scale (millimeter level) radio localization and tracking scheme-Hybrid Inertial Microwave Reflectometry-for radio frequency identification and other wireless systems. The scheme combines the backscattered radio frequency signal properties, such as received signal strength and received signal phase, along with reflected inertial data from a tag-mounted accelerometer sensor. Experimental results yield a mean error of 2 mm in ranging accuracy, with a 90% confidence interval of ±1 mm, while tracking a tag moving at a maximum speed of 1.4 m/s.