Estimation of ionospheric threat model parameters for GBAS using gnss data for Marmara Region

Date

2016

Author

Yeganehsahab, Amir

Metadata

Show full item record

Item Usage Stats

127
views

0
downloads

To establish a proper Ground-Based Augmentation System (GBAS), the estimation of ionospheric threat model parameters is of paramount importance. For this, it is also necessary to make use of precise ionospheric models in terms of local or regional coverages in order to generate Vertical Total Electron Content (VTEC). VTEC can be calculated from a local ionospheric model on the basis of a second order surface polynomial using GNSS data. Therefore, a Variance Component Estimation technique has been performed to weight different kind of observations from Global Positioning System (GPS) and GLObal NAvigation Satellite System (GLONASS). The VTEC parameters are estimated together with Differential Code Bias (DCB) parameters to get calibrated VTECs which in turn are needed for the estimation of correct ionospheric gradients. To validate the results visually and automatically, estimated VTEC values have been compared with that of Global Ionosphere Models (GIMs) provided by International GPS Service (IGS). The calculation of spatial ionospheric gradients is based on two different approaches, namely the Rate of Change and Station-Pair gradients which are referred to different geometrical concepts. The resulting gradients have been used to estimate the Ionospheric Threat Model Parameters for Ground Based Augmentation System (GBAS). From the estimation of Threat Model parameters can be concluded that both approaches provide consistent results. For the Marmara region, no significant high ionospheric gradient has been detected applying both approaches to GNSS data during geomagnetic storms between 2010- 2015. Consequently, estimated threat model parameters do not show considerable differences in this region.

Subject Keywords

Ionosphere., Ionospheric electron density., Global Positioning System., Geographic information systems.

URI

http://etd.lib.metu.edu.tr/upload/12620556/index.pdf
https://hdl.handle.net/11511/25925

Collections

Graduate School of Natural and Applied Sciences, Thesis

Suggestions

OpenMETU
Core

Non-parametric and semi-parametric regional modeling of the ionospheric vertical total electron content using ground-based GPS observations Durmaz, Murat; Karslıoğlu, Mahmut Onur; Department of Geodetic and Geographical Information Technologies (2013) Different global and regional models have been proposed for modeling of Vertical Total Electron Content(VTEC). Basis functions such as Spherical Harmonics and tensor products of univariate B-Splines are used for global and regional modeling respectively. The coefficients of the basis functions and Differential Code Biases (DCB) of satellites and receivers are treated as parameters and estimated from geometry-free linear combinations. In this work, a new approach based on non-parametric and semi-parametric m...
Positional uncertainty analysis using data uncertainy engine a case study on agricultural land parcels Urgancı, İlksen; Düzgün, H. Şebnem; Department of Geodetic and Geographical Information Technologies (2009) Most of spatial data extraction and updating procedures require digitization of geographical entities from satellite imagery. During digitization, errors are introduced by factors like instrument deficiencies or user errors. In this study positional uncertainty of geographical objects, digitized from high resolution Quickbird satellite imagery, is assessed using Data Uncertainty Engine (DUE). It is a software tool for assessing uncertainties in environmental data; and generating realisations of uncertain da...
Development of a quasi 2-DH model for numerical modeling of shoreline changes Özsoy, Can; Baykal, Cüneyt; Department of Civil Engineering (2021-2-15) The scope of this thesis is to develop a quasi-2-dimensional numerical model to numerically modeling shoreline response under wave action in the vicinity of various coastal defense implementation. The developed quasi-2-dimensional model is applicable in both the medium and the long term. The model is utilizing a spectral wave model, which solves the energy balance equation. Longshore sediment transport is solved through the bulk sediment transport formula, and it is distributed over the surf-zone. The aim i...
Improved viewshed analysis algorithms for avionics applications Özkıdık, Mustafa; Koçyiğit, Altan; Department of Information Systems (2019) Viewshed analysis is a common GIS capability used in various domains with various requirements. In avionics, viewshed analysis is a part of accuracy critical applications and the real time operating systems in embedded devices use preemptive scheduling algorithms to satisfy performance requirements. Therefore, to effectively benefit from the viewshed analysis, a method should be both fast and accurate. Although R3 algorithm is accepted as an accuracy benchmark, R2 algorithm with lower accuracy is preferred ...
Evaluating the mine plan alternatives with respect to bottom-up and top-down sustainability criteria Yaylaci, Evren Deniz; Düzgün, Hafize Şebnem (Elsevier BV, 2017-11-20) The previous researches on sustainability evaluation for the mining sector indicate that the tailor-made integrated frameworks should have the capabilities of integrating the stakeholder-focused information as effectively as operational information into the evaluation and reporting process. In this regard, this paper proposes an indicator-based quantitative evaluation framework for integrating the concerns and priorities of the local stakeholders into the evaluation of sustainability in the mining sector op...

Citation Formats

A. Yeganehsahab, “Estimation of ionospheric threat model parameters for GBAS using gnss data for Marmara Region,” M.S. - Master of Science, Middle East Technical University, 2016.