In 2009, the "Cooperative Network for GIOVE Observation" (CONGO) was initiated to enable a global tracking of the prototype Galileo satellites GIOVE-A and -B. In view of the further upcoming constellations BeiDou and QZSS as well as enhanced receiver capabilities, the network was later renamed to "Cooperative Network for GNSS Observation". The network is operated in cooperation with internal and external partners. DLR-interal cooperation partners are the Institute of Communications and Navigation and the Galileo Competence Center. External partners are mainly universities hosting GNSS equipment as given in the table below. Data of seven stations are publicly available at the data centers of the International GNSS Service (IGS). Another sever stations are for internal use only.
Selected stations deliver raw navigation data frames providing the basis for the analysis of modernized GNSS navigation signals The GNSS observation data recorded by these stations offer the basis for a wide range of scientific analysis:
Characterization of new GNSS signals, e.g., IRNSS L1 or GLONASS L1/L2 CDMA
Attitude determination of satellites equipped with two or three antenna transmitting navigation signal, e.g., QZSS and GLONASS K2
Modernized navigation messages like the GPS civil navigation message (CNAV) or GLONASS CDMA navigation messages
Orbit and clock determination of new satellites whose tracking is not sufficiently supported by publicly available GNSS data
Selected publications on these topics are given below.
Steigenberger, P., Montenbruck, O., Bradke, M., Ramatschi, M., and Hessels, U. (2022) Evaluation of earth rotation parameters from modernized GNSS navigation messages. GPS Solutions, 26(2), 50. https://doi.org/10.1007/s10291-022-01232-4
Steigenberger, P., Montenbruck, O., and Hessels, U. (2015) Performance Evaluation of the Early CNAV Navigation Message. Navigation, 62(3), 219–228. https://doi.org/10.1002/navi.111
Hauschild, A., Steigenberger, P., and Rodriguez-Solano, C. (2012) QZS-1 Yaw Attitude Estimation Based on Measurements from the CONGO Network. Navigation, 59(3).
Montenbruck, O., Hauschild, A., Steigenberger, P., Hugentobler, U., Teunissen, P., and Nakamura, S. (2012) Initial assessment of the COMPASS/BeiDou-2 regional navigation satellite system. GPS Solutions, 17(2), 211–222. https://doi.org/10.1007/s10291-012-0272-x
Montenbruck, O., Hauschild, A., and Hessels, U. (2011) Characterization of GPS/GIOVE sensor stations in the CONGO network. GPS Solutions, 15(3), 193–205. https://doi.org/10.1007/s10291-010-0182-8
Steigenberger, P., Hugentobler, U., Montenbruck, O., and Hauschild, A. (2011) Precise orbit determination of GIOVE-B based on the CONGO network. Journal of Geodesy, 85(6), 357–365. https://doi.org/10.1007/s00190-011-0443-5
Data availability
RINEX observation and navigation files
Daily GNSS observation and navigation files of the 7 CONGO stations contributing to the IGS are publicly available at the IGS data centers, e.g., CDDIS
Navigation data of all CONGO stations as well as additional stations provided by GFZ are used to generate a merged multi-GNSS broadcast ephemerides product in RINEX 4 format, labeled BRD4.
Montenbruck, O., & Steigenberger, P. (2022). BRD400DLR: DLR's merged multi-GNSS broadcast ephemeris product in RINEX 4.00 format, DLR/GSOC, https://doi.org/10.57677/BRD400DLR
