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Improving Ambiguity Resolution Rate with an Accurate Ionospheric Differential Correction

Published online by Cambridge University Press:  22 December 2008

Mardina Abdullah ,
Hal J. Strangeways  and
David M. A. Walsh
Mardina Abdullah*
Affiliation:
(Universiti Kebangsaan Malaysia)
Hal J. Strangeways
Affiliation:
(University of Leeds)
David M. A. Walsh
Affiliation:
(University of Leeds)
*
(Email: mardina@vlsi.eng.ukm.my)
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Abstract

Ambiguity resolution is essential for precise range determination. As it is difficult to process, a good ionospheric model is essential to get unambiguous results or to reduce time to solve the ambiguities. In this paper, a developed model to determine the differential ionospheric error to sub-centimetre accuracy is described. As a function of elevation angle and TEC, the model is applicable at any location and only requires a single frequency receiver provided the TEC over the reference station is known. It has been evaluated using real GPS measurements at spaced stations in Glasgow (UK) and Stirling (UK), where the results showed good correlation. It was found that the variance ratio and reference variance of the ambiguity resolution rate and the quality of the differential positioning solution are improved. Significant improvements of more than 50% have also been found by correcting the differential ionospheric delay in the measurements for the estimated positions.

Keywords

Ambiguity resolutionionosphereGPSTEC
Type
Research Article
Information
The Journal of Navigation , Volume 62 , Issue 1 , January 2009 , pp. 151 - 166
Copyright
Copyright © The Royal Institute of Navigation 2008

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References

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