RF Environment Sensing Using Transceivers in Motion

Abstract : We have developed methods for device-free localization (DFL) and tracking using transceivers in motion. Standard DFL systems use a large number of static transceivers which is problematic for applications which require rapid deployment. We propose that transceivers mounted on autonomous vehicles could be both quickly deployed and kept moving to sweep an area for changes in the channel that would indicate the location of moving people and objects. The challenge is that changes to channel measurements are introduced both by changes in the environment and from motion of the transceivers. In this project, we successfully demonstrate a method to detect human movement despite transceiver motion using ultra-wideband impulse radar (UWB-IR) transceivers. The measurements reliably detect a person's presence on a link line despite small-scale fading. We explore via multiple experiments the ability of mobile UWB-IR transceivers, moving outside of the walls of a room, to measure many lines crossing through the room and accurately locate a person inside within 0.25 m average error.