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A Study Of Direct Severe Space Weather Effects On GPS Ionospheric Delay

Published online by Cambridge University Press:  10 December 2007

Renato Filjar
Renato Filjar*
Affiliation:
(Kalinovac, Croatia)
*
(Email: renato.filjar@yahoo.co.uk)
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Abstract

Severe space weather conditions affect the performance of numerous modern technical systems, causing problems not only for national and global economies, but for everyday life as well. Satellite navigation systems are particularly vulnerable, despite the fact that systematic monitoring of space weather in general is still performed on a global scale. Space weather effect correction models applied within the standard satellite positioning service are not capable of tackling the effects of severe space weather conditions and local ionospheric characteristics. Severe space weather effects on the GPS ionospheric delay are intensely studied in order to provide advanced models of the space weather effects on GPS positioning performance.

Here one study of severe space weather conditions and its consequences on the GPS ionospheric delay in Croatia is presented. The study takes advantage of the availability of the space weather indices and the GPS pseudorange measurements (taken at the reference site at Osijek, Croatia) related to a major severe space weather event lasting from early October 2003 to late November 2003. This paper presents the reconstruction of the severe space weather conditions and the development of ionospheric disturbances. Based on these reconstructions, the dynamics of the GPS ionospheric delay has been derived. The comparison of actual (measured) and modelled (according to standard GPS model) GPS ionospheric delay has been performed, with the aims of identifying actual behaviour of GPS ionospheric delay and examining the ability of standard (Klobuchar) GPS model to describe the GPS ionospheric delay in severe space weather conditions. Two interesting experimental models derived from the data analysis are presented, addressing the direct relations between the GPS ionospheric delay and the parameters of space weather activity (sunspot number and solar flux), as observed at the reference station Osijek, Croatia.

The paper concludes with the plans for further research activities related to the regional GPS ionospheric delay model development for south-eastern Europe.

Keywords

Space weatherGPSIonospheric delayMathematical model
Type
Research Article
Information
The Journal of Navigation , Volume 61 , Issue 1 , January 2008 , pp. 115 - 128
Copyright
Copyright © The Royal Institute of Navigation 2007

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References

REFERENCES

Booker, H. G. (1954). Morphology of Ionospheric Storms. Proc. NAS, 40, pp 931–943.CrossRefGoogle Scholar
Davis, K. (1990). Ionospheric Radio. Peter Peregrinus Ltd. London, UK.CrossRefGoogle Scholar
Filjar, R., Kos., T. (2006). GPS Positioning Accuracy in Croatia during the Extreme Space Weather Conditions in September 2005. European Navigation Conference ENC 2006. Manchester, UK.Google Scholar
Filjar, R. (2001). Horizontal GPS Positioning Accuracy During the 1999 Solar Eclipse. The Journal of Navigation, 54:293–296. Cambridge University Press.CrossRefGoogle Scholar
Institut Geographique National. (2006). Available at: http://igs.ensg.ign.fr/, accessed on 1 November 2006.Google Scholar
Klobuchar, J. A. et al. (2002). Total Electron Content Effects on GNSS Augmentation System. Proc. of XXVIIth URSI General Assembly. Maastricht, Belgium. Available at: http://www.ursi.org/Proceedings/ProcGA02, accessed on 1 December 2006.Google Scholar
Klobuchar, J. A. (1987). Ionospheric Time-Delay Algorithm for Single-Frequency GPS Users. IEEE Trans. On Aerospace and Electronic Systems, 23(3), pp 325–331.CrossRefGoogle Scholar
Langley, R. B. (2000). GPS, the Ionosphere, and the Solar Maximum. GPS World, July 2000, pp 44–49.Google Scholar
Lockwood, M. et al. (1999). Predicting Solar Disturbance Effects on Navigation Systems. The Journal. of Navigation, 52, 203–216.CrossRefGoogle Scholar
McNamara, L. F. (1991). Ionosphere: Communications, Surveillance and Direction Finding. Krieger Publishing. Malabar, FL.Google Scholar
Misra, P., Enge., P. (2004). Global Positioning System: Signals, Measurements, and Performance (2nd printing). Ganga-Jamuna Press. Lincoln, MA.Google Scholar
National Weather Service. (2004). Intense Space Weather Storms October 19 – November 07, 2003. National Oceanic and Atmospheric Administration, US Department of Commerce. Silver Spring, MD. (Available at: http://www.sec.noaa.gov/AboutSEC/SWstorms_assessment.pdf, accessed on 1 November 2006.).Google Scholar
Oler, C. (2004). Prediction performance of space weather forecast centers following the extreme events of October and November 2003. Space Weather, 2, S08001, doi: 10.1029/2004SW000076.CrossRefGoogle Scholar
Parkinson, B. W., Spilker, J. J. (editors) (1996). Global Positioning System: Theory and Applications (Vol. I.). AIAA. Washington, DC.CrossRefGoogle Scholar
Sandford, W. H. (1999). The Impact on Solar Winds on Navigation Aids. The Journal. of Navigation, 52, 42–46.CrossRefGoogle Scholar
Space Physics Interactive Data Resource – SPIDR (National Geophysical Data Center, US National Oceanic and Atmospheric Administration – NOAA). (2006). Availbale at: http://spidr.ngdc.noaa.gov/spidr/index.jsp, accessed on 2 November 2006.Google Scholar
US National Geodetic Survey – CORS (Continuously Operating Reference Stations. (2006). Available at: http://www.ngs.noaa.gov/CORS/download2/, accessed on 2 November 2006.Google Scholar