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Analysis of Estimation in Time Delay using Klobuchar Algorithm

K.S.N.V Someswara Rao, B. SashiKanth, M.N.V Pavan Kumar, CH. Anusha


Various kinds of error factors prejudice the accuracy of the GPS navigation solution, among which the GPS signal delay by the ionosphere is the greatest after the elimination of selective availability. This delay can be estimated using Klobuchar Model, which estimate ionospheric time delay up to 50% or more, on an rms basis which is vital to give the appropriate user position for single frequency GPS receivers. In this paper, using the Klobuchar algorithm, the ionospheric time delay (IDE), ionospheric range delay and Total Electron Content of ionosphere are estimated for the entire day of a typical day i.e. September 1st 2013. The observation data required for implementation of the algorithm is collected from Scripps Orbitary And Permanent Array Center (SOPAC) for a typical International GNSS Service (IGS) permanent tracking/reference station, i.e National Geophysical Research Institute (NGRI),INDIA.


Klobuchar Model, Ionospheric Error, GNSS

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