CDDIS: NASA's Archive of Space Geodesy Data
High-rate QZSS broadcast ephemeris data

doi: 10.5067/GNSS/gnss_highrate_q_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, High-rate QZSS broadcast ephemeris data, Greenbelt, MD, USA:NASA Crustal Dynamics Data Information System (CDDIS), Accessed [[enter user data access date]] at doi:10.5067/GNSS/gnss_highrate_q_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: High-rate QZSS broadcast ephemeris data
  • Format: RINEX V2, UNIX compressed ASCII
  • Spatial Coverage: 90.0N to -90.0S, 180.0E to -180.0W
  • Temporal Coverage: 2001-05-01 to present
  • Temporal Resolution:15 minutes
  • File Size: 250 Kbytes/15-minute file
  • Platforms: Multiple GNSS

Description

The 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.

This dataset consists of ground-based Global Navigation Satellite System (GNSS) Quasi-Zenith Satellite System (QZSS) Broadcast Ephemeris Data (sub-hourly files) 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 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. The sub-hourly QZSS broadcast ephemeris files contain 15 minutes of QZSS broadcast navigation data in RINEX format from a global permanent network of ground-based receivers, one file per 15 minutes per site.

Data Access

The high-rate GNSS QZSS broadcast ephemeris data are online:

in subdirectories by year and day of year as follows:

YYYY/DDD/YYq/HH/mmmmDDDHMM.YYq.Z,

as described in the table below.

Code Meaning
YYYY4-digit year
DDD3-digit day of year
YY2-digit year
HH 2-digit hour of day (00, 01, ..., 23)
mmmm 4-character site monument name
H 1-character hour of day (a, b, ..., x)
MM 2-digit minute of hour (00, 15, 30, 45)
.Z UNIX compressed file

Documentation

http://cddis.nasa.gov/Data_and_Derived_Products/GNSS/high-rate_data.html