<abstract xml:lang="en" xmlns="http://www.w3.org/1999/xhtml"><p>The ionospheric delay is the major current source of potential range delay for single-frequency GNSS users (Kunches and Klobuchar, 2001). Single-frequency GNSS users are in most need of an ionospheric model to eliminate the ionospheric delay to a high degree of accuracy. GPS system uses the Klobuchar model for this task, which its coefficients are sent through the GPS navigation message to GPS users. Klobuchar model uses the Ionospheric Corrections Algorithm (ICA) (Klobuchar, 1987) designed to account for approximately 50% (rms) of the ionospheric range delay. NeQuick model is a model of the electron concentration profile that has been developed in the framework of the European Commission COST action 251. NeQuick model is being proposed for single-frequency operation in the European Galileo GNSS system (Radicella et al., 2003). A comparison study between the behaviour of the GPS Single-frequency ionospheric modelling (Klobuchar model) and the Galileo proposed approach for this task (NeQuick model) will be presented in this paper. The range delay correction by the two models has been assessed using the IGS-Global Ionospheric Maps for three different-latitude stations to reflect different geographic ionospheric activity states. The study was carried out over three different months that each of them reflects a different state of solar activity, which is a major indication for the ionospheric development state.</p></abstract>

The ionospheric delay is the major current source of potential range delay for single-frequency GNSS users (Kunches and Klobuchar, 2001). Single-frequency GNSS users are in most need of an ionospheric model to eliminate the ionospheric delay to a high degree of accuracy. GPS system uses the Klobuchar model for this task, which its coefficients are sent through the GPS navigation message to GPS users. Klobuchar model uses the Ionospheric Corrections Algorithm (ICA) (Klobuchar, 1987) designed to account for approximately 50% (rms) of the ionospheric range delay. NeQuick model is a model of the electron concentration profile that has been developed in the framework of the European Commission COST action 251. NeQuick model is being proposed for single-frequency operation in the European Galileo GNSS system (Radicella et al., 2003). A comparison study between the behaviour of the GPS Single-frequency ionospheric modelling (Klobuchar model) and the Galileo proposed approach for this task (NeQuick model) will be presented in this paper. The range delay correction by the two models has been assessed using the IGS-Global Ionospheric Maps for three different-latitude stations to reflect different geographic ionospheric activity states. The study was carried out over three different months that each of them reflects a different state of solar activity, which is a major indication for the ionospheric development state.

Comparison Of GPS/Galileo Single Frequency Ionospheric Models With Vertical Tec Maps

Aswan-Faculty of Engineering, South Valley University, Egypt

Artificial Satellites

The ionospheric delay is the major current source of potential range delay for single-frequency GNSS users (Kunches and Klobuchar, 2001). Single-frequency GNSS...

Comparison Of GPS/Galileo Single Frequency Ionospheric Models With Vertical Tec Maps

Published Online: May 29, 2009

Page range: 75 - 90

DOI: https://doi.org/10.2478/v10018-009-0008-5

Keywords
GPS, Galileo, Ionospheric modelling

This content is open access.

Comparison Of GPS/Galileo Single Frequency Ionospheric Models With Vertical Tec Maps

Published Online: May 29, 2009

Page range: 75 - 90

DOI: https://doi.org/10.2478/v10018-009-0008-5

KeywordsGPS, Galileo, Ionospheric modelling

This content is open access.

Keywords
GPS, Galileo, Ionospheric modelling