doi: 10.5067/GNSS/GNSS_IGSDCB_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 Differential Code Bias Product, Greenbelt, MD, USA:NASA Crustal Dynamics Data Information System (CDDIS), Accessed [[enter user data access date]] at doi: 10.5067/GNSS/GNSS_IGSDCB_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 Differential Code Bias Product available from the Crustal Dynamics Data Information System (CDDIS)
• Format: IGS SINEX Bias
• Spatial Coverage: 90.0 to -90.0, 180.0 to -180.0
• Temporal Coverage: 2013-01-01 to present
• Temporal Resolution: Daily
• File Size: 50 kbytes/file
• Platforms: GPS, GLONASS, Galileo, BeiDou

Description

This dataset consists of differential code biases (DCBs) from a network of ground-based Global Navigation Satellite System (GNSS) stations and available 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.

DCBs are the systematic errors, or biases, between two GNSS code observations at the same or different frequencies. DCBs are required for code-based positioning of GNSS receivers, extracting ionosphere total electron content (TEC), and other applications. Proper knowledge of DCBs is crucial to many navigation applications but also non-navigation applications such as ionospheric analysis and time transfer. With all of the new signals offered by modernized and new GNSS constellations, analysts now require a comprehensive multi-GNSS DCB product.

As part of the IGS Multi-GNSS Experiment (MGEX) two different DCB products are determined by two analysis groups: Institute of Geodesy and Geophysics (IGG) of the Chinese Academy of Sciences (CAS) in Wuhan and the Deutsche Forschungsanstalt für Luftund Raumfahrt (DLR) in Germany.

The satellite and station biases computed by the Institute of Geodesy and Geophysics (IGG) of the Chinese Academy of Sciences (CAS) in Wuhan are generated on a daily basis with a latency of 2-3 days and made available in daily BSX files. The constellations and signals analyzed by the IGG CAS are:

Constellation	Analyzed Signals
GPS	C1C,C1W,C2L/S/X,C2W,C5Q/X
GLO	C1C,C1P,C2C,C2P
GAL	C1C/X,C5Q/X,C7Q/X,C8Q/X
BDS	C2I,C6I,C7I

The DLR product is updated on a 3-monthly basis and comprises weekly averages of the satellite biases. In addition a full set of daily satellite and station biases is provided for reference purposes and trend analyses. The constellations and signals analyzed by the DLR are:

Constellation	Analyzed Signals
GPS	C1C,C1W,C2L/S/X,C2W,C5Q/X
GLO	C1C,C1P,C2C,C2P
GAL	C1C/X,C5Q/X,C7Q/X,C8Q/X), in addition GAL(C6C) since Q2/2017
BDS	C2I,C6I,C7I

Data Access

The GGNSS Differential Code Bias Products are online:

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

CAS0MGXRAP_YYYYDDD0000_01D_01D_DCB.BSX.gz
DLR0MGXFIN_YYYYDDD0000_03L_07D_DCB.BSX.gz
DLR0MGXFIN_YYYYDDD0000_03L_01D_DCB.BSX.gz

where:

Code	Meaning
YYYY	4-digit year of start epoch
DDD	3-digit day-of-year of start epoch
gz	compression file type

Documentation

https://cddis.nasa.gov/Data_and_Derived_Products/GNSS/gnss_differential_code_bias_product.html

Wang N., Yuan Y., Li Z., Montenbruck O., Tan B. (2016) Determination of differential code biases with multi-GNSS observations, Journal of Geodesy, Vol. 90, No. 3, pp. 209-228, DOI 10.1007/s00190-015-0867-4

Montenbruck O., Hauschild A., Steigenberger P. (2014), Differential Code Bias Estimation using Multi-GNSS Observations and Global Ionosphere Maps, Navigation - Journal of the ION, Vol. 61, No. 3, pp. 191-201, DOI 10.1002/navi.64