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Decoded orbit solution (30 second) from IGS real-time product streams

doi: 10.5067/GNSS/gnss_igsrtorb_001

Data Center Citation

Noll, Carey E., The Crustal Dynamics Data Information System: A resource to support scientific analysis using space geodesy, Advances in Space Research, Volume 45, Issue 12, 15 June 2010, Pages 1421-1440, ISSN 0273-1177, http://dx.doi.org/10.1016/j.asr.2010.01.018.

Data Citation

International GNSS Service, Decoded orbit solution (30 second) from IGS real-time product streams, Greenbelt, MD, USA:NASA Crustal Dynamics Data Information System (CDDIS), Accessed [[enter user data access date]] at doi: 10.5067/GNSS/gnss_igsrtorb_001.

Other standard citation formats may be used for this data set and can be found at the DOI Citation Formatter website.

More information about CDDIS data citations and acknowledgments is available.


  • Name: Decoded orbit solution (30 second) from IGS real-time product streams
  • Format: RTCM
  • Spatial Coverage: 90.0 to -90.0, 180.0 to -180.0
  • Temporal Coverage: 2009-01-01 to present
  • Temporal Resolution:real-time
  • File Size: N/A
  • Platforms: GNSS (e.g., GPS)


The IGS real-time products can be used to determine precise coordinates of the observing stations, gravity field parameters, and Earth orientation parameters. The IGS derived products are essential for Earth science research; multi-disciplinary positioning, navigation, and timing (PNT) applications; and education.

This derived product set consists of Global Navigation Satellite System satellite orbit products (daily files, generated daily) from the real-time IGS analysis center submissions available from NASA Crustal Dynamics Data Information System (CDDIS). GNSS satellites provide autonomous geo-spatial positioning with global coverage. GNSS data sets from ground receivers at the CDDIS consist primarily of the data from the U.S. Global Positioning System (GPS) and the Russian GLObal NAvigation Satellite System (GLONASS). Since 2011, the CDDIS GNSS archive includes data from other GNSS (Europe’s Galileo, China’s Beidou, Japan’s Quasi-Zenith Satellite System/QZSS, the Indian Regional Navigation Satellite System/IRNSS, and worldwide Satellite Based Augmentation Systems/SBASs), which are similar to the U.S. GPS in terms of the satellite constellation, orbits, and signal structure.These orbit products are generated from real-time data streams in support of the IGS Real-Time Service. The real-time observation data from a global permanent network of ground-based receivers are transmitted from the CDDIS in 1 to multi-second intervals in raw receiver or RTCM (Radio Technical Commission for Maritime Services) format.

These real-time data are utilized to generate near real-time product streams. The real-time products consist of GNSS satellite orbit and clock corrections to the broadcast ephemeris. These correction streams are formatted according to the RTCM SSR standard for State Space Representation and are broadcast using the NTRIP protocol. The product streams are combination solutions generated by processing individual real time solutions from participating IGS Real-time Analysis Centers (ACs). The effect of combining the different AC solutions is a more reliable and stable performance than that of any single AC's product. This derived product solution is one of the RTS solutions generated by decoding the real-time product streams. These files use the real-time data streams that are referred to the satellite center-of-mass (CoM). These orbit products have been provided in support of the IGS Real-Time Service (previously Real-Time Pilot Project) since February 2009, prior to the availability of real-time product streams. This combination is a daily solution available approximately one to three days after the end of the previous UTC day. All orbit solution files utilize the SP3 format and span 24 hours from 00:00 to 23:45 UTC.

Data Access

The decoded orbit solution (30 second) from IGS real-time product streams products are online:


Append the following file names to the starting directory


as described in the table below.

Code Meaning
Dday of week (0-6, 7 indicates weekly)
.Z Unix compressed file