Check out the new USENIX Web site.

USENIX Home . About USENIX . Events . membership . Publications . Students
3rd International Conference on Mobile Systems, Applications, and Services — Abstract

Pp. 233–246 of the Proceedings

Accuracy Characterization for Metropolitan-scale Wi-Fi Localization

Yu-Chung Cheng, Intel Research Seattle and University of California, San Diego; Yatin Chawathe and Anthony LaMarca, Intel Research Seattle; John Krumm, Microsoft Research

Abstract

Location systems have long been identified as an important component of emerging mobile applications. Most research on location systems has focused on precise location in indoor environments. However, many location applications (for example, location-aware web search) become interesting only when the underlying location system is available ubiquitously and is not limited to a single office environment. Unfortunately, the installation and calibration overhead involved for most of the existing research systems is too prohibitive to imagine deploying them across, say, an entire city. In this work, we evaluate the feasibility of building a wide-area 802.11 Wi-Fi-based positioning system. We compare a suite of wireless-radio-based positioning algorithms to understand how they can be adapted for such ubiquitous deployment with minimal calibration. In particular, we study the impact of this limited calibration on the accuracy of the positioning algorithms. Our experiments show that we can estimate a user's position with a median positioning error of 13-40Êmeters (depending upon the characteristics of the environment). Although this accuracy is lower than existing positioning systems, it requires substantially lower calibration overhead and provides easy deployment and coverage across large metropolitan areas.
  • View the full text of this paper in HTML and PDF.
    Click here if you have forgotten your password Until June 2006, you will need your USENIX membership identification in order to access the full papers. The Proceedings are published as a collective work, © 2005 by the USENIX Association. All Rights Reserved. Rights to individual papers remain with the author or the author's employer. Permission is granted for the noncommercial reproduction of the complete work for educational or research purposes. USENIX acknowledges all trademarks within this paper.

  • If you need the latest Adobe Acrobat Reader, you can download it from Adobe's site.
To become a USENIX Member, please see our Membership Information.

?Need help? Use our Contacts page.

Last changed: 24 May 2005 aw
Technical Program
MobiSys '05 Home
USENIX home