SnapLoc: An Ultra-Fast UWB-Based Indoor Localization System for an Unlimited Number of Tags

Bernhard Großwindhager, Michael Stocker, Michael Rath, Carlo Alberto Boano, Kay Uwe Römer

Research output: Chapter in Book/Report/Conference proceedingConference paperpeer-review

Abstract

A large body of work has shown that ultra-wideband (UWB) technology enables accurate indoor localization and tracking thanks to its high time-domain resolution. Existing systems, however, are typically designed to localize only a limited number of tags, and involve the exchange of several messages following a given schedule. As a result, the scalability of current solutions in terms of tag density is limited, as well as their efficiency and responsiveness. In this paper, we present SnapLoc, a UWB-based indoor localization system that allows an unlimited number of tags to self-localize at a theoretical upper bound of 2.3 kHz. In SnapLoc, a tag obtains the responses from multiple anchors simultaneously. Based on these signals, the tag derives the time difference of arrival between anchors and estimates its position. Therefore, SnapLoc does not require tags to actively transmit packets, but to receive only a single message. This allows tags to passively localize themselves and ensures that the performance of SnapLoc does not degrade with high node densities. Moreover, due to the (quasi-)simultaneous responses, a tight clock synchronization between anchors is not needed. We have implemented SnapLoc on a low-cost platform based on the De-cawave DW1000 radio and solved limitations in the transceiver's timestamp resolution to sustain a high localization accuracy. An experimental evaluation shows that SnapLoc exhibits a 90% error and median error of 33 cm and 18 cm, respectively, hence enabling decimeter-level accuracy at fast update rates for countless tags.
Original languageEnglish
Title of host publicationSnapLoc: An Ultra-Fast UWB-Based Indoor Localization System for an Unlimited Number of Tags
Pages61-72
Number of pages12
ISBN (Electronic)978-1-4503-6284-9
Publication statusPublished - 16 Apr 2019
Event18th ACM/IEEE International Conference on Information Processing in Sensor Networks: IPSN 2019 - Montreal, Canada
Duration: 16 Apr 201918 Apr 2019

Conference

Conference18th ACM/IEEE International Conference on Information Processing in Sensor Networks
Abbreviated titleIPSN
Country/TerritoryCanada
CityMontreal
Period16/04/1918/04/19

Keywords

  • ultra wideband technology
  • localization
  • scalability
  • channel impulse response

Fields of Expertise

  • Information, Communication & Computing

Cite this