Abstract
Many types of human activities involve interaction with passive objects. Thus, by wirelessly sensing human interaction with them, one can infer activities at a fine resolution, enabling a new wave of ubiquitous computing applications. In this paper, we propose LiveTag to achieve this vision. LiveTag is a fully passive, thin metal tag that can be printed on paper-like substrates and attached to objects. It has no batteries, silicon chips, or discrete electronic components. But when touched by fingers, it disturbs the ambient WiFi channel in a deterministic way. Multiple metallic structures can be printed on the same tag to create unique touch points. Further, LiveTag incorporates customized multi-antenna beamforming algorithms that allow WiFi receivers to sense the tag and discriminate the touch events amid multipath reflections/interferences. Our prototypes of LiveTag have verified its feasibility and performance. We have further applied LiveTag to real-world usage scenarios to showcase its effectiveness in sensing human-object interaction.
BibTeX
@inproceedings{livetag_NSDI2018,
author = {Chuhan Gao and Yilong Li and Xinyu Zhang},
title = {Livetag: sensing human-object interaction through passive chipless WiFi tags},
year = {2018},
isbn = {9781931971430},
publisher = {USENIX Association},
address = {USA},
booktitle = {Proceedings of the 15th USENIX Conference on Networked Systems Design and Implementation (NSDI 2018)},
pages = {533–546},
numpages = {14},
location = {Renton, WA, USA},
series = {NSDI'18}
}