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International GNSS Service (IGS): Structure, Data, and Products

  • March 2012
DOI:10.13140/RG.2.2.36805.09447/1
  • Conference: Internal Student Seminars
  • At: Geomatics Engineering Department
  • Affiliation: University of Isfahan
Authors:
Amir Allahvirdi-Zadeh at Curtin University
Amir Allahvirdi-Zadeh
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Abstract

I introduced the International GNSS Service in the internal students' seminar at the University of Isfahan: The International GNSS Service (IGS) has ensured open access, high-quality GNSS data products since 1994. These products enable access to the definitive global reference frame for scientific, educational, and commercial applications – a tremendous benefit to the public, and a key support element for scientific advancements. The IGS at a Glance A voluntary federation of over 200 self-funding agencies, universities, and research institutions in more than 100 countries; working together to provide the highest precision GPS satellite orbits in the world. Providing free and open access to the highest precision products available for scientific advancement and public benefit. These products support a wide variety of applications that touch millions of users in virtually all segments of the global economy Producing products that support the realization of the International Terrestrial Reference Frame while providing access to tracking data from over 400 worldwide reference stations Working for the continuous development of new applications and products through Working Groups and Pilot Projects Supporting geodetic research and scholarly publications Functioning as a component of the Global Geodetic Observing System (GGOS) and member of the World Data System (WDS).
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IGS
DATA
PRODUCT
DATA
Ground
observations
Low-earth orbiter
observations
PRODUCT
GPS Satellite Ephemerides/
Satellite & Station Clocks
GLONASS Satellite Ephemerides
Geocentric Coordinates of IGS
Tracking Stations (>250 sites)
Earth Rotation Parameters:
Polar Motion (PM)
Polar Motion Rates (PM rate)
Length-of-day (LOD)
Atmospheric Parameters
Ground
observations
GPS & GLONASS
GLONASS Broadcast
ephemerides
Meteorological
Low earth orbiter
observations
GPS Satellite Ephemerides/
Satellite & Station Clocks
GLONASS Satellite
Ephemerides
Geocentric Coordinates of
IGS Tracking Stations (>250
sites)
Earth Rotation Parameters:
Polar Motion (PM)
Polar Motion Rates (PM rate)
Length of day (LOD)
Atmospheric
Parameters
GLONASSGPS &
IGS RINEX
. .
:
1. Latency: ~1 day
Update: Daily
Sample Interval: 30 s
Archive Location: CDDIS(US-MD) SOPAC(US-CA) IGN(FR)
2. Latency: ~1 hour
Update: hourly
Sample Interval: 30 s
Archive Location: CDDIS(US-MD SOPAC(US-CA) IGN(FR
3. Latency: ~15 min
Update: 15 min
Sample Interval: 1 s
Archive Location: CDDIS(US-MD) IGN(FR
GPS Broadcast ephemerides
IGS .
:
GPS Broadcast
ephemerides
Latency: ~1 day
Update: Daily
Archive Location: CDDIS(US-MD) SOPAC(US-CA) IGN(FR)
File extension: brdcddd0.yyn
GPS .
. :
GPS Broadcast ephemerides
IGS :
1. Latency: ~1 day
Update: Daily
Archive Location: CDDIS(US-MD) SOPAC(US-CA) IGN(FR)
File extension: brdcddd0.yyn
2. Latency: ~1 hour
Update: hourly
Archive Location: CDDIS(US-MD SOPAC(US-CA) IGN(FR
File extension: brdcddd0.yyn
3. Latency: ~15 min
Update: 15 min
Archive Location: CDDIS(US-MD) IGN(FR
File extension: brdcddd0.yyn
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The presentations of the other international services are available in [1], [2], and [3]. Study [4] for the
quality control of the GPS data. Different combinations of noises in the time series of the IGS
permanent station are discussed in [5].
References
[1] Allahvirdi-Zadeh, A., (2012). International Earth rotation and Reference Systems Service (IERS):
Structure, Data, Products, Applications. In Internal Student Seminars, Geomatics Engineering
Department, University of Isfahan. DOI: 10.13140/RG.2.2.26817.40800/1
(http://dx.doi.org/10.13140/RG.2.2.26817.40800/1)
[2] Allahvirdi-Zadeh, A., (2012). A deep look at the International Laser Ranging Service (ILRS). In
Internal Student Seminars, Geomatics Engineering Department, University of Isfahan. DOI:
10.13140/RG.2.2.17589.93923/1 (http://dx.doi.org/10.13140/RG.2.2.17589.93923/1)
[3] Allahvirdi-Zadeh, A., (2012). International Doris Service (IDS): Data and Products. In Internal
Student Seminars, Geomatics Engineering Department, University of Isfahan. DOI:
10.13140/RG.2.2.27905.99681 (http://dx.doi.org/10.13140/RG.2.2.27905.99681)
[4] Allahvirdi-Zadeh, A., (2011). GPS Quality Control. In Internal Student Seminars, Geomatics
Engineering Department, University of Isfahan. DOI: 10.13140/RG.2.2.19189.01764
(http://dx.doi.org/10.13140/RG.2.2.19189.01764)
[5] Allahvirdi-Zadeh, A., (2011). Detect and Analysis of Noise with Different Combinations of Time
Series in IGS Permanent Stations. In Internal Student Seminars, Geomatics Engineering Department,
University of Isfahan. DOI: 10.13140/RG.2.2.21286.16965/2
(http://dx.doi.org/10.13140/RG.2.2.21286.16965/2)
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