Journal ArticleDOI
Modelling of low-latitude ionosphere using modified planar fit method for GAGAN
TLDR
In this article, a modified planar fit model is applied for GPS aided geo augmented navigation (GAGAN) data on similar lines as was done for WAAS and the results are encouraging.Abstract:
Several countries have been developing satellite-based augmentation systems (SBAS) for improving positional accuracy of global positioning system (GPS). India is also developing one such system popularly known as GPS aided geo augmented navigation (GAGAN) system. Modelling of ionospheric effects is one of the major challenges in developing precise and reliable GAGAN. The high values of total electron content (TEC), the large diurnal and seasonal variability and intense irregularities present in the low-latitude ionosphere, lead to unacceptable positional errors in GAGAN service region. Todd Walter et al. of Stanford University, USA have made significant contribution in the area of SBAS ionospheric grid modelling by developing the popularly known planar fit model. It is reported by Walter et al. (2000) that a constant decorrelation value of 35 cm was proposed over the wide area augmentation system (WAAS) service region. To provide accurate estimation of ionospheric delays at user ionospheric pierce points (IPP) during a storm or intense irregularities, an irregularity detector and a decorrelation adaptor are incorporated in the modelling. As planar fit model is not adequate to model intense irregularities of Indian ionosphere, a modified planar fit model is applied for GAGAN data on similar lines as was done for WAAS and the results are encouraging.read more
Citations
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Journal ArticleDOI
SHPTS: towards a new method for generating precise global ionospheric TEC map based on spherical harmonic and generalized trigonometric series functions
TL;DR: In this article, a spherical harmonic plus generalized trigonometric series functions (SHPTS) approach was proposed to improve the accuracy and resolution of global ionospheric TEC map (GIM).
SHPTS: Towards a new method for generating precise global ionospheric TEC maps based on spherical harmonic and generalized trigonometric series functions
TL;DR: In this paper, a spherical harmonic plus generalized trigonometric series functions (SHPTS) approach was proposed to improve the accuracy and resolution of global ionospheric TEC map (GIM).
Journal ArticleDOI
Satellite Radiolocalization From GPS to GNSS and Beyond: Novel Technologies and Applications for Civil Mass Market
TL;DR: The scope of this paper is to provide readers with a clear focus about the potentialities of current and forthcoming GNSSs and associated technologies in a renewed mass-market perspective, and with the seamless integration of satellite-based navigation with other technologies in order to provide reliable position information also in hostile environments.
Journal ArticleDOI
Performance evaluation of selected ionospheric delay models during geomagnetic storm conditions in low‐latitude region
TL;DR: In this article, the performance of three prominent ionospheric models was investigated for adverse ionosphere conditions using 17 GPS TEC stations data, and the models characterized the ionosphere disturbances due to two magnetic storms well.
Journal ArticleDOI
Performance evaluation of ionospheric time delay forecasting models using GPS observations at a low-latitude station
TL;DR: In this paper, the authors proposed a short/long-term ionospheric delay forecasting model for Indian sub-continent by considering day-to-day, monthly and seasonal ionosphere TEC variations.
References
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Journal ArticleDOI
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TL;DR: The Wide Area Augmentation System (WAAS) is being deployed by the Federal Aviation Administration to augment the Global Positioning System (GPS) and will provide an accurate position fix from satellites to an unlimited number of aircraft across the nation.
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