A technique for routinely updating the ITU-R database using radio occultation electron density profiles

Autores
Brunini, Claudio Antonio; Azpilicueta, Francisco Javier; Nava, Bruno
Año de publicación
2013
Idioma
inglés
Tipo de recurso
artículo
Estado
versión publicada
Descripción
Well credited and widely used ionospheric models, such as the International Reference Ionosphere or NeQuick, describe the variation of the electron density with height by means of a piecewise profile tied to the F2-peak parameters: the electron density, NₘF2, and the height, hₘF2. Accurate values of these parameters are crucial for retrieving reliable electron density estimations from those models. When direct measurements of these parameters are not available, the models compute the parameters using the so-called ITU-R database, which was established in the early 1960s. This paper presents a technique aimed at routinely updating the ITU-R database using radio occultation electron density profiles derived from GPS measurements gathered from low Earth orbit satellites. Before being used, these radio occultation profiles are validated by fitting to them an electron density model. A re-weighted Least Squares algorithm is used for down-weighting unreliable measurements (occasionally, entire profiles) and to retrieve NₘF2 and hₘF2 values—together with their error estimates—from the profiles. These values are used to monthly update the database, which consists of two sets of ITU-R-like coefficients that could easily be implemented in the IRI or NeQuick models. The technique was tested with radio occultation electron density profiles that are delivered to the community by the COSMIC/FORMOSAT-3 mission team. Tests were performed for solstices and equinoxes seasons in high and low-solar activity conditions. The global mean error of the resulting maps—estimated by the Least Squares technique—is between 0.5 × 10¹⁰ and 3.6 × 10¹⁰ elec/m⁻³ for the F2-peak electron density (which is equivalent to 7 % of the value of the estimated parameter) and from 2.0 to 5.6 km for the height (∼2 %).
Facultad de Ciencias Astronómicas y Geofísicas
Materia
Astronomía
Ionosphere
F2-peak parameters
ITU-R maps updating
International Reference Ionosphere (IRI)
NeQuick
Radio-occultation
Nivel de accesibilidad
acceso abierto
Condiciones de uso
http://creativecommons.org/licenses/by/4.0/
Repositorio
SEDICI (UNLP)
Institución
Universidad Nacional de La Plata
OAI Identificador
oai:sedici.unlp.edu.ar:10915/146348

id SEDICI_c4568918497c180bed9788ea5fca9c93
oai_identifier_str oai:sedici.unlp.edu.ar:10915/146348
network_acronym_str SEDICI
repository_id_str 1329
network_name_str SEDICI (UNLP)
spelling A technique for routinely updating the ITU-R database using radio occultation electron density profilesBrunini, Claudio AntonioAzpilicueta, Francisco JavierNava, BrunoAstronomíaIonosphereF2-peak parametersITU-R maps updatingInternational Reference Ionosphere (IRI)NeQuickRadio-occultationWell credited and widely used ionospheric models, such as the International Reference Ionosphere or NeQuick, describe the variation of the electron density with height by means of a piecewise profile tied to the F2-peak parameters: the electron density, NₘF2, and the height, hₘF2. Accurate values of these parameters are crucial for retrieving reliable electron density estimations from those models. When direct measurements of these parameters are not available, the models compute the parameters using the so-called ITU-R database, which was established in the early 1960s. This paper presents a technique aimed at routinely updating the ITU-R database using radio occultation electron density profiles derived from GPS measurements gathered from low Earth orbit satellites. Before being used, these radio occultation profiles are validated by fitting to them an electron density model. A re-weighted Least Squares algorithm is used for down-weighting unreliable measurements (occasionally, entire profiles) and to retrieve NₘF2 and hₘF2 values—together with their error estimates—from the profiles. These values are used to monthly update the database, which consists of two sets of ITU-R-like coefficients that could easily be implemented in the IRI or NeQuick models. The technique was tested with radio occultation electron density profiles that are delivered to the community by the COSMIC/FORMOSAT-3 mission team. Tests were performed for solstices and equinoxes seasons in high and low-solar activity conditions. The global mean error of the resulting maps—estimated by the Least Squares technique—is between 0.5 × 10¹⁰ and 3.6 × 10¹⁰ elec/m⁻³ for the F2-peak electron density (which is equivalent to 7 % of the value of the estimated parameter) and from 2.0 to 5.6 km for the height (∼2 %).Facultad de Ciencias Astronómicas y Geofísicas2013-09info:eu-repo/semantics/articleinfo:eu-repo/semantics/publishedVersionArticulohttp://purl.org/coar/resource_type/c_6501info:ar-repo/semantics/articuloapplication/pdf813-823http://sedici.unlp.edu.ar/handle/10915/146348enginfo:eu-repo/semantics/altIdentifier/issn/0949-7714info:eu-repo/semantics/altIdentifier/issn/1432-1394info:eu-repo/semantics/altIdentifier/doi/10.1007/s00190-013-0648-xinfo:eu-repo/semantics/openAccesshttp://creativecommons.org/licenses/by/4.0/Creative Commons Attribution 4.0 International (CC BY 4.0)reponame:SEDICI (UNLP)instname:Universidad Nacional de La Platainstacron:UNLP2025-09-29T11:32:12Zoai:sedici.unlp.edu.ar:10915/146348Institucionalhttp://sedici.unlp.edu.ar/Universidad públicaNo correspondehttp://sedici.unlp.edu.ar/oai/snrdalira@sedici.unlp.edu.arArgentinaNo correspondeNo correspondeNo correspondeopendoar:13292025-09-29 11:32:13.129SEDICI (UNLP) - Universidad Nacional de La Platafalse
dc.title.none.fl_str_mv A technique for routinely updating the ITU-R database using radio occultation electron density profiles
title A technique for routinely updating the ITU-R database using radio occultation electron density profiles
spellingShingle A technique for routinely updating the ITU-R database using radio occultation electron density profiles
Brunini, Claudio Antonio
Astronomía
Ionosphere
F2-peak parameters
ITU-R maps updating
International Reference Ionosphere (IRI)
NeQuick
Radio-occultation
title_short A technique for routinely updating the ITU-R database using radio occultation electron density profiles
title_full A technique for routinely updating the ITU-R database using radio occultation electron density profiles
title_fullStr A technique for routinely updating the ITU-R database using radio occultation electron density profiles
title_full_unstemmed A technique for routinely updating the ITU-R database using radio occultation electron density profiles
title_sort A technique for routinely updating the ITU-R database using radio occultation electron density profiles
dc.creator.none.fl_str_mv Brunini, Claudio Antonio
Azpilicueta, Francisco Javier
Nava, Bruno
author Brunini, Claudio Antonio
author_facet Brunini, Claudio Antonio
Azpilicueta, Francisco Javier
Nava, Bruno
author_role author
author2 Azpilicueta, Francisco Javier
Nava, Bruno
author2_role author
author
dc.subject.none.fl_str_mv Astronomía
Ionosphere
F2-peak parameters
ITU-R maps updating
International Reference Ionosphere (IRI)
NeQuick
Radio-occultation
topic Astronomía
Ionosphere
F2-peak parameters
ITU-R maps updating
International Reference Ionosphere (IRI)
NeQuick
Radio-occultation
dc.description.none.fl_txt_mv Well credited and widely used ionospheric models, such as the International Reference Ionosphere or NeQuick, describe the variation of the electron density with height by means of a piecewise profile tied to the F2-peak parameters: the electron density, NₘF2, and the height, hₘF2. Accurate values of these parameters are crucial for retrieving reliable electron density estimations from those models. When direct measurements of these parameters are not available, the models compute the parameters using the so-called ITU-R database, which was established in the early 1960s. This paper presents a technique aimed at routinely updating the ITU-R database using radio occultation electron density profiles derived from GPS measurements gathered from low Earth orbit satellites. Before being used, these radio occultation profiles are validated by fitting to them an electron density model. A re-weighted Least Squares algorithm is used for down-weighting unreliable measurements (occasionally, entire profiles) and to retrieve NₘF2 and hₘF2 values—together with their error estimates—from the profiles. These values are used to monthly update the database, which consists of two sets of ITU-R-like coefficients that could easily be implemented in the IRI or NeQuick models. The technique was tested with radio occultation electron density profiles that are delivered to the community by the COSMIC/FORMOSAT-3 mission team. Tests were performed for solstices and equinoxes seasons in high and low-solar activity conditions. The global mean error of the resulting maps—estimated by the Least Squares technique—is between 0.5 × 10¹⁰ and 3.6 × 10¹⁰ elec/m⁻³ for the F2-peak electron density (which is equivalent to 7 % of the value of the estimated parameter) and from 2.0 to 5.6 km for the height (∼2 %).
Facultad de Ciencias Astronómicas y Geofísicas
description Well credited and widely used ionospheric models, such as the International Reference Ionosphere or NeQuick, describe the variation of the electron density with height by means of a piecewise profile tied to the F2-peak parameters: the electron density, NₘF2, and the height, hₘF2. Accurate values of these parameters are crucial for retrieving reliable electron density estimations from those models. When direct measurements of these parameters are not available, the models compute the parameters using the so-called ITU-R database, which was established in the early 1960s. This paper presents a technique aimed at routinely updating the ITU-R database using radio occultation electron density profiles derived from GPS measurements gathered from low Earth orbit satellites. Before being used, these radio occultation profiles are validated by fitting to them an electron density model. A re-weighted Least Squares algorithm is used for down-weighting unreliable measurements (occasionally, entire profiles) and to retrieve NₘF2 and hₘF2 values—together with their error estimates—from the profiles. These values are used to monthly update the database, which consists of two sets of ITU-R-like coefficients that could easily be implemented in the IRI or NeQuick models. The technique was tested with radio occultation electron density profiles that are delivered to the community by the COSMIC/FORMOSAT-3 mission team. Tests were performed for solstices and equinoxes seasons in high and low-solar activity conditions. The global mean error of the resulting maps—estimated by the Least Squares technique—is between 0.5 × 10¹⁰ and 3.6 × 10¹⁰ elec/m⁻³ for the F2-peak electron density (which is equivalent to 7 % of the value of the estimated parameter) and from 2.0 to 5.6 km for the height (∼2 %).
publishDate 2013
dc.date.none.fl_str_mv 2013-09
dc.type.none.fl_str_mv info:eu-repo/semantics/article
info:eu-repo/semantics/publishedVersion
Articulo
http://purl.org/coar/resource_type/c_6501
info:ar-repo/semantics/articulo
format article
status_str publishedVersion
dc.identifier.none.fl_str_mv http://sedici.unlp.edu.ar/handle/10915/146348
url http://sedici.unlp.edu.ar/handle/10915/146348
dc.language.none.fl_str_mv eng
language eng
dc.relation.none.fl_str_mv info:eu-repo/semantics/altIdentifier/issn/0949-7714
info:eu-repo/semantics/altIdentifier/issn/1432-1394
info:eu-repo/semantics/altIdentifier/doi/10.1007/s00190-013-0648-x
dc.rights.none.fl_str_mv info:eu-repo/semantics/openAccess
http://creativecommons.org/licenses/by/4.0/
Creative Commons Attribution 4.0 International (CC BY 4.0)
eu_rights_str_mv openAccess
rights_invalid_str_mv http://creativecommons.org/licenses/by/4.0/
Creative Commons Attribution 4.0 International (CC BY 4.0)
dc.format.none.fl_str_mv application/pdf
813-823
dc.source.none.fl_str_mv reponame:SEDICI (UNLP)
instname:Universidad Nacional de La Plata
instacron:UNLP
reponame_str SEDICI (UNLP)
collection SEDICI (UNLP)
instname_str Universidad Nacional de La Plata
instacron_str UNLP
institution UNLP
repository.name.fl_str_mv SEDICI (UNLP) - Universidad Nacional de La Plata
repository.mail.fl_str_mv alira@sedici.unlp.edu.ar
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