Rotation sensing using passive RFID tags

Shuozhe Li, Lili Qiu, Swadhin Pradhan

Abstract: Rotational movement is important in many applications, yet has been under-explored. In this paper, we explore the feasibility of using a single RFID reader antenna to simultaneously sense rotation and translation movement (i.e., rotation axis, rotation speed, and translation speed). We exploit the polarization in RFID to enable motion sensing. We develop an analytical model to capture the impact of polarization on the received signal and an optimization framework to incorporate the model to estimate the movement. We implement our system, Tag-based Inertial Measurement Unit (TIMU), and demonstrate its effectiveness through an extensive evaluation. To our knowledge, this is the first system that tracks general motion using a single RFID reader antenna.