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Positional Accuracy of Assisted GPS Data from High-Sensitivity GPS-enabled Mobile Phones

Published online by Cambridge University Press:  07 June 2011

Paul A. Zandbergen*
Affiliation:
(Department of Geography, University of New Mexico)
Sean J. Barbeau
Affiliation:
(Center for Urban Transportation Research, University of South Florida)
*

Abstract

Utilizing both Assisted GPS (A-GPS) techniques and new high-sensitivity embedded GPS hardware, mobile phones are now able to achieve positioning in harsh environments such as urban canyons and indoor locations where older embedded GPS chips could not. This paper presents an empirical analysis of the positional accuracy of location data gathered using a high-sensitivity GPS-enabled mobile phone. The performance of the mobile phone is compared to that of regular recreational grade GPS receivers. Availability of valid GPS position fixes on the mobile phones tested was consistently close to 100% both outdoors and indoors. During static outdoor testing, positions provided by the mobile phones revealed a median horizontal error of between 5·0 and 8·5 m, substantially larger than those for regular autonomous GPS units by a factor of 2 to 3. Horizontal errors during static indoor testing were larger compared to outdoors, but the difference in accuracy between mobile phones and regular GPS receivers was reduced. Despite the modest performance of A-GPS on mobile phones, testing under various conditions revealed that very large errors are not very common. The maximum horizontal error during outdoor testing never exceeded 30 metres and during indoor testing never exceeded 100 metres. Combined with the relatively consistent availability of valid GPS position fixes under varying conditions, the current study has confirmed the reliability of A-GPS on mobiles phones as a source of location information for a range of different LBS applications.

Type
Research Article
Copyright
Copyright © The Royal Institute of Navigation 2011

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References

REFERENCES

Aguilar, D. P., Barbeau, S. J., Labrador, M. A., Perez, A., Perez, R. A., and Winters, P. L.. (2007a). Quantifying the position accuracy of real-time multi-modal transportation behavior data collected using GPS-enabled mobile phones. Transportation Research Record: Journal of the Transportation Research Board, 1992, 5460.CrossRefGoogle Scholar
Aguilar, D. P., Barbeau, S. J., Perez, R. A., Labrador, M. A., and Winters, P. L.. (2007b). A comparison of fix times and estimated accuracies in Application Programming Interfaces (APIs) for GPS enabled mobile phones. Proceedings of the 11th World Conference on Transport Research, Berkeley, CA.Google Scholar
ABI Research. (2006a). Personal locator services to reach more than 20 million North American consumers by 2011. ABI Research press release, November 28, 2006. Accessed online at 01/31/2010 at http://www.abiresearch.com/abiprdisplay.jsp?pressid=766.Google Scholar
ABI Research. (2006b). GPS-enabled location based services (LBS) subscribers will total 315 million in five years. ABI Research press release, September 27, 2006. Accessed online at 01/31/2010 at http://www.abiresearch.com/abiprdisplay.jsp?pressid=731Google Scholar
ABI Research. (2006c). GPS devices and systems will generate revenues of $240 billion by 2013. ABI Research press release, April 28, 2006. Accessed online at 01/31/2010 at http://www.abiresearch.com/abiprdisplay.jsp?pressid=1115Google Scholar
Barbeau, S. J., Labrador, M. A., Winters, P. L., Perez, R.A, Georggi, N.. 2008. Location API 2.0 for J2ME – A new standard in location for Java-enabled mobile phones. Computer Communications, 31(6): 10911103.CrossRefGoogle Scholar
FCC. (2009). Enhanced 911 – Wireless Services. Federal Communications Commission. Accessed online 01/31/2010 at http://www.fcc.gov/pshs/services/911services/enhanced911/Welcome.htmlGoogle Scholar
FCC. (2000). Guidelines for testing and verifying the accuracy of wireless E911 location systems. Federal Communications Commission. OET Bulletin No. 71, April 12, 2009.Google Scholar
GPS World. (2008). GPS handset market poised for huge expansion. May 9, 2008. Questex Media Group, Inc.Google Scholar
ITU. (2009). World Telecommunications/ICT Indicators Database 2009. International Telecommunications Union, United Nations.Google Scholar
Kupper, A. (2005). Location Based Services: Fundamentals and operation. John Wiley & Sons.CrossRefGoogle Scholar
Watson, J. R. A. (2005). High-sensitivity GPS L1 signal analysis for indoor channel modeling. University of Calgary, Department of Geomatics Engineering, UCGE Reports Number 20215.Google Scholar
MacGougan, G., Lachapelle, G., Klukas, R., Siu, K., Garin, L., Shewfelt, J., and Cox, G.. (2002). Performance of a stand-alone high-sensitivity receiver. GPS Solutions, 6(3): 179195.Google Scholar
Porcino, D. (2001). Location of third generation mobile devices: A comparison between terrestrial and satellite positioning systems. IEEE 53rd Vehicular Technology Conference, 4: 29702974.Google Scholar
Schön, S., and Bielenberg, O.. (2008). On the capability of high sensitivity GPS for precise indoor positioning. Proceedings of the 5th Workshop on Positioning, Navigation and Communication, IEEE, pp. 121127.CrossRefGoogle Scholar
Serr, K., Windholz, T., and Weber, K.. (2006). Comparing GPS receivers: A field study. URISA Journal, 18(2): 1923.Google Scholar
Synovate. (2009). Synovate mobile phones survey. Accessed online 01/31/2010 at http://www.synovate.com/insights/infact/issues/200909/Google Scholar
Van Diggelen, F. (2002). Indoor GPS theory and implementation,” IEEE Position, Location & Navigation Symposium, 240247.CrossRefGoogle Scholar
Vittorini, L., and Robinson, B.. (2003). Optimizing indoor GPS performance. GPS World. November.Google Scholar
Wieser, A. (2006). High-sensitivity GNSS: The trade-off between availability and accuracy. 12th FIG Symposium, International Federation of Surveyors, Baden.Google Scholar
Wing, M. G., Eklund, A., and Kellog, L. D.. (2005). Consumer-grade Global Positioning System (GPS) accuracy and reliability. Journal of Forestry, 103: 169173.CrossRefGoogle Scholar
Zandbergen, P.A. 2009. Accuracy of iPhone locations: A comparison of assisted-GPS, WiFi and cellular positioning. Transactions in GIS, 13(s1): 5–25.CrossRefGoogle Scholar