Twenty-Five Years of the International GNSS Service

For over twenty-five years, the International Global Navigation Satellite System (GNSS) Service (IGS) has carried out its mission to advocate for and provide freely and openly available high-precision GNSS data and products.The IGS is an essential component of the IAG&#8217;s Global Geodetic Observing System (GGOS), where it facilitates cost-effective geometrical linkages with and among other precise geodetic observing techniques, including: Satellite Laser Ranging (SLR), Very Long Baseline Interferometry (VLBI), and Doppler Orbitography and Radio Positioning Integrated by Satellite (DORIS). These linkages are fundamental to generating and accessing the International Terrestrial Reference Frame (ITRF).&#160; As it enters its second quarter-century, the IGS is evolving into a truly multi-GNSS service, and at its heart is a strong culture of sharing expertise, infrastructure, and other resources for the purpose of encouraging global best practices for developing and delivering GNSS data and products all over the world.This poster will present an update on current IGS products and operations, as well as highlights on recent organizational developments and community activities. The impacts and benefits of global cooperation and openly available data will be emphasized, and information about the IGS stations and network, contributions to the International Terrestrial Reference Frame solutions, and product applications will be presented. A summary of IGS products, with emphasis on analysis, coordination, applications, and their availability will be described. Information about efforts to form new groups supporting product generation within IGS open data and product policies will be included. Information about the themes and topics of discussion for the upcoming 2020 IGS Workshop in Boulder, Colorado, USA will also be provided.

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AVALIAÇÃO DO DESEMPENHO DOS SISTEMAS GPS E GLONASS NO POSICIONAMENTO POR PONTO PRECISO, COMBINADOS E INDIVIDUALMENTE.

Boletim de Ciências Geodésicas ◽

10.1590/s1982-21702016000200015 ◽

2016 ◽

Vol 22 (2) ◽

pp. 265-281 ◽

Cited By ~ 2

Author(s):

Bruno Guimarães Ventorim ◽

William Rodrigo Dal Poz

Keyword(s):

Reference Frame ◽

Global Positioning System ◽

Terrestrial Reference Frame ◽

Positioning System ◽

International Gnss Service ◽

International Terrestrial Reference Frame ◽

Global Positioning ◽

Quality Check

Este trabalho visa avaliar o desempenho dos sistemas GLONASS (Global'naya Navigatsionnay Sputnikovaya Sistema), GPS (Global Positioning System) e o uso combinado de ambos sistemas em diferentes latitudes, utilizando o serviço de Posicionamento por Ponto Preciso CSRS-PPP. Para isso foram selecionadas 16 estações da rede IGS (International GNSS Service), das quais foram utilizados os dados GNSS no formato RINEX do mês de agosto de 2014 e editados no TEQC (Translation, Editing, and Quality Check), obtendo arquivos com intervalos de 30 e 45 minutos, contendo apenas dados GPS, dados GLONASS e dados dos dois sistemas. As coordenadas estimadas no CSRS-PPP foram comparadas com as coordenadas de referência obtidas no sítio do ITRF (International Terrestrial Reference Frame), possibilitando o cálculo da acurácia do PPP com uso de dados GPS e GLONASS, separadamente e em conjunto. Após o cálculo das acurácias para cada dia de agosto, outliers foram detectados e eliminados utilizando o método boxplot com o uso do programa R. Verificou-se que o uso combinado do GPS e GLONASS, para todos as estações, proporcionou resultados mais acurados. Além disso, pode-se destacar a potencialidade do GLONASS, que apresentou desempenho superior ao do GPS na maioria das estações.

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The Contribution of LARES to Global Climate Change Studies With Geodetic Satellites

Volume 2: Integrated System Design and Implementation; Structural Health Monitoring; Bioinspired Smart Materials and Systems; Energy Harvesting ◽

10.1115/smasis2015-8924 ◽

2015 ◽

Cited By ~ 3

Author(s):

Giampiero Sindoni ◽

Claudio Paris ◽

Cristian Vendittozzi ◽

Erricos C. Pavlis ◽

Ignazio Ciufolini ◽

...

Keyword(s):

Reference Frame ◽

Earth Science ◽

Global Climate ◽

Temporal Variations ◽

Terrestrial Reference Frame ◽

Global Navigation Satellite Systems ◽

Satellite Systems ◽

Long Baseline ◽

Geophysical Processes ◽

Global Navigation Satellite

Satellite Laser Ranging (SLR) makes an important contribution to Earth science providing the most accurate measurement of the long-wavelength components of Earth’s gravity field, including their temporal variations. Furthermore, SLR data along with those from the other three geometric space techniques, Very Long Baseline Interferometry (VLBI), Global Navigation Satellite Systems (GNSS) and DORIS, generate and maintain the International Terrestrial Reference Frame (ITRF) that is used as a reference by all Earth Observing systems and beyond. As a result we obtain accurate station positions and linear velocities, a manifestation of tectonic plate movements important in earthquake studies and in geophysics in general. The “geodetic” satellites used in SLR are passive spheres characterized by very high density, with little else than gravity perturbing their orbits. As a result they define a very stable reference frame, defining primarily and uniquely the origin of the ITRF, and in equal shares, its scale. The ITRF is indeed used as “the” standard to which we can compare regional, GNSS-derived and alternate frames. The melting of global icecaps, ocean and atmospheric circulation, sea-level change, hydrological and internal Earth-mass redistribution are nowadays monitored using satellites. The observations and products of these missions are geolocated and referenced using the ITRF. This allows scientists to splice together records from various missions sometimes several years apart, to generate useful records for monitoring geophysical processes over several decades. The exchange of angular momentum between the atmosphere and solid Earth for example is measured and can be exploited for monitoring global change. LARES, an Italian Space Agency (ASI) satellite, is the latest geodetic satellite placed in orbit. Its main contribution is in the area of geodesy and the definition of the ITRF in particular and this presentation will discuss the improvements it will make in the aforementioned areas.

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ITRF2014: A new release of the International Terrestrial Reference Frame modeling nonlinear station motions

Journal of Geophysical Research Solid Earth ◽

10.1002/2016jb013098 ◽

2016 ◽

Vol 121 (8) ◽

pp. 6109-6131 ◽

Cited By ~ 352

Author(s):

Zuheir Altamimi ◽

Paul Rebischung ◽

Laurent Métivier ◽

Xavier Collilieux

Keyword(s):

Reference Frame ◽

Terrestrial Reference Frame ◽

International Terrestrial Reference Frame

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Erratum to: Determination of a terrestrial reference frame via Kalman filtering of very long baseline interferometry data

Journal of Geodesy ◽

10.1007/s00190-016-0953-2 ◽

2016 ◽

Vol 90 (12) ◽

pp. 1329-1329 ◽

Cited By ~ 1

Author(s):

Benedikt Soja ◽

Tobias Nilsson ◽

Kyriakos Balidakis ◽

Susanne Glaser ◽

Robert Heinkelmann ◽

...

Keyword(s):

Reference Frame ◽

Kalman Filtering ◽

Very Long Baseline Interferometry ◽

Terrestrial Reference Frame ◽

Long Baseline

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Geocentric Terrestrial Reference Frame Accuracy: DSN Spacecraft Tracking and VLBI/Lunar Laser Ranging

Symposium - International Astronomical Union ◽

10.1017/s0074180900119370 ◽

1988 ◽

Vol 128 ◽

pp. 115-120 ◽

Cited By ~ 1

Author(s):

A. E. Niell

Keyword(s):

Reference Frame ◽

Terrestrial Reference Frame ◽

Spin Axis ◽

Laser Ranging ◽

Lunar Laser Ranging ◽

Deep Space Network ◽

Long Baseline ◽

Lunar Laser ◽

Spacecraft Tracking ◽

Geocentric Coordinates

From a combination of 1) the location of McDonald Observatory from Lunar Laser Ranging, 2) relative station locations obtained from Very Long Baseline Interferometry (VLBI) measurements, and 3) a short tie by traditional geodesy, the geocentric coordinates of the 64 m antennas of the NASA/JPL Deep Space Network are obtained with an orientation which is related to the planetary ephemerides and to the celestial radio reference frame. Comparison with the geocentric positions of the same antennas obtained from tracking of interplanetary spacecraft shows that the two methods agree to 20 cm in distance off the spin axis and in relative longitude. The orientation difference of a 1 meter rotation about the spin axis is consistent with the error introduced into the tracking station locations due to an error in the ephemeris of Jupiter.

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