Defense Technical Information Center (DTIC) · 1975 · 33 citations · 0 references
Natural SciencesEarth SciencesGeodesyGlobal Navigation Satellite SystemsTime Series AnalysisIonospheric ElectrodynamicsIonospheric PropagationGlobal Ionospheric ModelingGlobal Positioning SystemIonospheric DelayIonospheric Delay CorrectionIonospheric Delay EstimationIonospheric Delay MitigationIonospheric Delay ModelingIonospheric Error Modeling
A first-order model algorithm designed to reduce ionospheric time- delay errors by approximately 50% rms on a world-wide basis for single frequency users of the Global Positioning System/NAVSTAR is described. The algorithm was designed for greatest accuracy during times of day when ionospheric time-delay errors are expected to be largest. The algorithm is available in several options from one which requires only a monthly mean solar-flux value to one which requires 9 daily or monthly update coefficients. Several approximations also are made in the geometry calculations to further reduce operational user computer storage and running time requirements.