mTrack: High-Precision Passive Tracking Using Millimeter Wave Radios

Radio-based passive-object sensing can enable a new form of pervasive user-computer interface. Prior work has employed various wireless signal features to sense objects under a set of predefined, coarse motion patterns. But an operational UI, like a trackpad, often needs to identify fine-grained, arbitrary motion. This paper explores the feasibility of tracking a passive writing object (e.g., pen) at subcentimeter precision. We approach this goal through a practical design, mTrack, which uses highly-directional 60 GHz millimeterwave radios as key enabling technology. mTrack runs a discrete beam scanning mechanism to pinpoint the object’s initial location, and tracks its trajectory using a signal-phase based model. In addition, mTrack incorporates novel mechanisms to suppress interference from background reflections, taking advantage of the short wavelength of 60 GHz signals. We prototype mTrack and evaluate its performance on a 60 GHz reconfigurable radio platform. Experimental ...

• Type: Journal
• Year: 2015
• Where: MOBICOM
• Authors: Teng Wei, Xinyu Zhang
• Keywords: Communications, MOBICOM 2015