Orientation sensing using backscattered phase from multi-antenna tag at 5.8 GHz

Abstract

Object localization is one of the most important applications of RFID technology. In this paper, we demonstrate how fine-scale orientation can be estimated from a multi-antenna backscatter tag. Three basic orientation changes - tag roll, pitch and yaw - were considered, where roll and pitch maneuvers were successfully identified from the direction of phase rotation. Moreover, an inclination of 5° in roll and pitch maneuvers was successfully identified by measuring the phase difference with 15% and 8% error respectively. The analysis can be extended to any amount of inclination.