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State-of-the-art RFID localization systems fall under two categories. The first category operates with off-the-shelf narrowband RFID tags but makes restrictive assumptions on the environment or the tag’s movement patterns. The second category does not make such restrictive assumptions; however, it requires designing new ultra-wideband hardware for RFIDs and uses the large bandwidth to directly compute a tag’s 3D location. Hence, while the first category is restrictive, the second one requires replacing the billions of RFIDs already produced and deployed annually. This paper presents RFind, a new technology that brings the benefits of ultra-wideband localization to the billions of RFIDs in today’s world. RFind does not require changing today’s passive narrowband RFID tags. Instead, it leverages their underlying physical properties to emulate a very large bandwidth and uses it for localization. Our empirical results demonstrate that RFind can emulate over 220MHz of bandwidth on tags designed with a communication bandwidth of only tens to hundreds of kHz, while remaining compliant with FCC regulations. This, combined with a new super-resolution algorithm over this bandwidth, enables RFind to perform 3D localization with sub-centimeter accuracy in each of the x/y/z dimensions, without making any restrictive assumptions on the tag’s motion or the environment.
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Fine-grained RFID Localization via Ultra-wideband Emulation
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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- Award ID(s):
- 1739723
- PAR ID:
- 10059095
- Date Published:
- Journal Name:
- ACM MobiCom
- Page Range / eLocation ID:
- 116 to 118
- 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
- Conference Paper:
- https://doi.org/10.1145/3123878.3132006
