Total Electron Content reconstruction using triple frequency GNSS signals
type: CreativeWork
description: Nowadays, Global Navigation Satellite System (GNSS) provide accurate three dimensional positioning and navigation anywhere and anytime on the Earth’s surface and are being utilized in numerous civilian and military applications. The US Global Positioning System (GPS) is currently being modernized to transmit radio signals on an additional third frequency, while the European Galileo is a newly developed system which will transmit on three civil frequency bands. One of the major error sources affecting GNSS is the delay caused when the signals pass through the ionosphere on their way to the Earth’s surface. This delay is inversely proportional to the square of the carrier frequency, and directly proportional to the Total Electron Content (TEC) of the ionosphere. In the last 20 years, several techniques using dual frequency GNSS measurements have been developed to estimate the TEC. With these techniques, systematic errors are confined to at least - 2.5 and 2.5 TECU for a mid-latitude site, and to at least - 5.5 and 5 TECU for a low-latitude location. In the last decades, knowledge about the ionosphere has grown considerably thanks to the use of GNSS measurements, and in turn the GNSS have highly benefited from this improved knowledge. Nowadays the availability of triple frequency GNSS signals enables the development of new processing techniques. We have therefore dedicated this work to developing a TEC reconstruction methodology based on triple frequency GNSS measurements and aimed at improving the accuracy of the final TEC values with regards to existing techniques. The structure of this study is as follows. Firstly, we provide information about GNSS, focusing on concepts, definitions and assumptions which will be used throughout this study. Then, we introduce the concepts of ionospheric propagation of radio signals and give a review of the literature on existing techniques used to extract the TEC with dual frequency GNSS measurements. We further present the complete …
abstract: Nowadays, Global Navigation Satellite System (GNSS) provide accurate three dimensional positioning and navigation anywhere and anytime on the Earth’s surface and are being utilized in numerous civilian and military applications. The US Global Positioning System (GPS) is currently being modernized to transmit radio signals on an additional third frequency, while the European Galileo is a newly developed system which will transmit on three civil frequency bands. One of the major error sources affecting GNSS is the delay caused when the signals pass through the ionosphere on their way to the Earth’s surface. This delay is inversely proportional to the square of the carrier frequency, and directly proportional to the Total Electron Content (TEC) of the ionosphere. In the last 20 years, several techniques using dual frequency GNSS measurements have been developed to estimate the TEC. With these techniques, systematic errors are confined to at least - 2.5 and 2.5 TECU for a mid-latitude site, and to at least - 5.5 and 5 TECU for a low-latitude location. In the last decades, knowledge about the ionosphere has grown considerably thanks to the use of GNSS measurements, and in turn the GNSS have highly benefited from this improved knowledge. Nowadays the availability of triple frequency GNSS signals enables the development of new processing techniques. We have therefore dedicated this work to developing a TEC reconstruction methodology based on triple frequency GNSS measurements and aimed at improving the accuracy of the final TEC values with regards to existing techniques. The structure of this study is as follows. Firstly, we provide information about GNSS, focusing on concepts, definitions and assumptions which will be used throughout this study. Then, we introduce the concepts of ionospheric propagation of radio signals and give a review of the literature on existing techniques used to extract the TEC with dual frequency GNSS measurements. We further present the complete …
author: Spits, Justine
language: en
keywords: ionosphere, TEC, GPS, Galileo, multi-frequency, Physical, chemical, mathematical & earth Sciences, Earth sciences & physical geography, Physique, chimie, mathématiques & sciences de la terre, Sciences de la terre & géographie physique
license: http://purl.org/coar/access_right/c_abf2
date published: 2012-01-25
date modified: 2026-07-24T02:49:14Z
provider: Université de Liège
publisher: Networked Digital Library of Theses and Dissertations
type: WebPage
source organization: ULiège - Université de Liège