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CDDIS: NASA's Archive of Space Geodesy Data
Hourly 30-second GLONASS broadcast ephemeris data

doi: 10.5067/GNSS/glonass_hourly_b_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, https://doi.org/10.1016/j.asr.2010.01.018.

Data Citation

International GNSS Service (IGS). 1992. Hourly 30-Second combined GLONASS broadcast ephemeris data [online]. Available from the NASA Crustal Dynamics Data Information System DAAC, Greenbelt, MD, USA at: DOI: 10.5067/GNSS/glonass_hourly_b_001, Accessed [[enter user data access date]].

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: Hourly 30-second combined GLONASS broadcast ephemeris data available from the Crustal Dynamics Data Information System (CDDIS)
  • Format: RINEX V2, UNIX compressed ASCII
  • Spatial Coverage: 90.0N to -90.0S, 180.0E to -180.0W
  • Temporal Coverage: 2010-09-23 to present
  • Temporal Resolution: Hourly
  • File Size: 60 Kbytes/day
  • Platforms: GLONASS

Description

GNSS receivers collect the signals from orbiting satellites to determine their location in three dimensions and calculate precise time. GNSS receivers detect, decode, and process both pseudorange (code) and phase transmitted by the GNSS satellites. The satellites transmit the ranging codes on two or more radio-frequency carriers, allowing the locations of GNSS receivers to be determined with varying degrees of accuracy, depending on the receiver and post-processing of the data. The receivers also calculate current local time to high precision facilitating time synchronization applications.

The combined GLONASS broadcast ephemeris file is generated on an hourly basis from all hourly RINEX V2 navigation files archived at the CDDIS. The hourly navigation file contains all broadcast messages with the TOE of the day that are available when the file is created at the top of the hour. The file is updated each hour with new navigation messages.

At the end of the UTC day, when the final version of the file is generated, the file is copied to the daily directories and becomes the "daily" broadcast ephemeris file.

Data Access

The hourly 30-second GNSS GLONASS broadcast ephemeris data are online:

in subdirectories by year and day of year:

Append the following directory and file names to the starting directory using the format codes in the table below:

YYYY/DDD/hourDDD0.YYg.gz

Code Meaning
YYYY4-digit year
DDD 3-digit day of year
YY2-digit year
.gz Compressed file

Documentation

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