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This demo presents RFind, a system that enables fine-grained RFID localization via ultra-wideband emulation. RFind operates by measuring the time-of-flight -- i.e., the time it takes the signal to travel from an antenna to an RFID tag. To do so, it emulates an ultra-wide bandwidth on today's narrowband RFIDs without requiring any hardware modification to the tags. It then uses the large emulated bandwidth to estimate the time-of-flight and localize RFIDs. In contrast to past RFID localization proposals, RFind can operate in multipath-rich environments without reference tags and without requiring tag or antenna motion. The demo will allow users to move RFID-tagged objects to any location in line-of-sight, non-line-of-sight, and multi-path rich settings and check that the system can accurately localize the objects.
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Building MechanoBeat: Instrumenting Mechanical "Heartbeats" on Everyday Objects for User Interaction
Knowing how and when people interact with their surroundings is crucial for constructing dynamic and intelligent environments. Despite the importance of this problem, an attainable and simple solution is still lacking. Current solutions often require powered sensors on monitored objects or users themselves. Many such systems use batteries [1-3], which are costly and time consuming to replace. Some powered systems connect to the grid, which may save swapping batteries, but at the price of restricted placement options. Other solutions use passive tags on monitored objects or require no tags at all, but many of these systems have prohibitive characteristics. For instance, camera-based systems [4,5] generally will not work if their view is occluded. Many other systems that rely on passive tags or do not use tags require direct line-of-sight or close proximity to work. As such, our goal was to design and develop small, cheap, easy-to-install tags that do not require any batteries, silicon chips or discrete electronic components, which can be monitored without direct line-of-sight.
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- Award ID(s):
- 2320678
- PAR ID:
- 10481787
- Publisher / Repository:
- ACM
- Date Published:
- Journal Name:
- GetMobile: Mobile Computing and Communications
- Volume:
- 26
- Issue:
- 4
- ISSN:
- 2375-0529
- Page Range / eLocation ID:
- 5 to 13
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1145/3583571.3583573
