doi: 10.5067/GNSS/gnss_igsusum_001

• Data Center Citation
• Data Citation
• Summary
• Description
• Data Access
• Documentation

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, GNSS Ultra-Rapid Combined Orbit Solution Summary Product, Greenbelt, MD, USA: NASA Crustal Dynamics Data Information System (CDDIS), Accessed [[enter user data access date]] at doi:10.5067/GNSS/gnss_igsusum_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.

Summary

• Name: GNSS Ultra-Rapid Combined Orbit Solution Summary Product available from the Crustal Dynamics Data Information System (CDDIS)
• Format: Text format, UNIX compressed ASCII
• Spatial Coverage: 90.0 to -90.0, 180.0 to -180.0
• Temporal Coverage: 2000-09-17 to present
• Temporal Resolution: Daily
• File Size: 50 Kbytes/day
• Platforms: GPS

Description

The IGS ultra-rapid orbit/clock/ERP products can be used to determine precise coordinates of the observing stations, gravity field parameters, and Earth orientation parameters. The IGS ultra-rapid products are the basis for the IGS reference frame and are intended for those applications demanding high consistency and quality. The IGS ultra-rapid products are available for near-real time use.

This derived product set consists of Global Navigation Satellite System Rapid Orbit/Reference Frame Product Summary from the 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. Analysis Centers (ACs) of the International GNSS Service (IGS) retrieve GNSS data on regular schedules to produce GNSS derived products. The IGS Analysis Center Coordinator (ACC) uses these individual AC solutions to generate the official IGS ultra-rapid combined orbit and ERP products. The ultra-rapid orbit and ERP is a sub-daily solution, released four times per day, at 03:00, 09:00, 15:00, and 21:00 UTC (prior to GPS week 1267 they were released twice daily). The solution summary file details information about the generation of the daily rapid products. The reduced latency on availability of these products allows for significantly improved orbit predictions and reduced errors for user applications.

Data Access

GNSS Ultra-Rapid Combined Orbit Solution Summary Products (GPS and GPS+GLONASS solutions) are online:

Append the following directory and file names to the starting directory:

WWWW/iguWWWWD_HH.sum.Z

as described in the table below.

Code	Meaning
WWWW	GPS week
D	day of week (0-6, 7 indicates weekly)
HH	hour of day (00, 06, 12, 18)
.Z	UNIX compressed file

Documentation

http://cddis.nasa.gov/Data_and_Derived_Products/GNSS/GNSS_data_and_product_archive.html