The Multi-GNSS Experiment (MGEX) has been set-up by the IGS to track, collate and analyze all available GNSS signals. This includes signals from the BeiDou, Galileo and QZSS systems, as well as from modernized GPS and GLONASS satellites and any space-based augmentation system (SBAS) of interest. Analysis centers will attempt to estimate inter-system calibration biases, compare equipment performance and further develop processing software capable of handling multiple GNSS observation data.MGEX observation files are available from various repositories hosted by the Crustal Dynamics Data Information System (CDDIS), Institut Géographique National (IGN), and Bundesamt für Kartographie und Geodäsie (BKG). The archives provide daily RINEX files at 30s update rate as well as high-rate (1 Hz) files for selected stations. The RINEX3 format is supported as the primary data format in view of its capability to handle all required constellations and observation types. An overview of tracked satellites and supported observation types for all MGEX stations is provided in a dedicated RINEX Observation File Summary maintained by the Astronomical Institute of the University of Bern.
RINEX Transition PlanIn the frame of the RINEX transition plan the IGS pursues the integration of multi-GNSS observation and navigation data in RINEX3 format and RINEX2 data from legacy stations. Users are encouraged to adapt their processing tools to the new file naming convention, which will ultimately supersede the old "8.3" naming scheme. The new file names comprise a 9-char station+country identification, an 11-digit start epoch, as well as two 3-char/digit fields indicating the nominal duration and sampling. By way of example, MAS100ESP_R_20142350000_01D_30S_MO.crx.gz denotes a gzipped daily, Hatanaka compressed observation file with 30-s sampling for the IGS MAS1 station in Spain. Compared to the old convention (mas12350.14d.Z) the new files names enable a clear distinction of multiple data files delivered by a single station. Also, the extened station names will cause less conflicts than the current 4-char designations. A detailed specification of the new file naming scheme is provided as part of the RINEX3 Standard.
NotesMGEX observation and navigation data are provided on a best-effort basis and may not offer the same level of consistency, quality and availability as legacy GPS/GLO data sets from the core IGS network. RINEX3 files in the MGEX repository may be generated
- within the receiver,
- from offline conversion of raw receiver data by the station provider using vendor-specific or proprietary offline tools, or
- from RTCM3-MSM real-time data streams using BKG's BNC software.
- Insonsistency of implemented features and RINEX version number (3.01, 3.02, 3.03)
- Absence of mandatory header lines (e.g. phase alignment information or GLONASS slot numbers)
- Use of improper observation type designations (e.g., C5X instead of C5Q for pilot-only tracking of the L5/E5a signal)
- Differences in observation values between data from RTCM3-MSM streams and unprocessed receiver data.
- Inconsistent observation types for BeiDou B1 observations due to inconsistent definitions in recent RINEX versions (C2I in RINEX 3.01 and 3.03 vs. C1I in RINEX 3.02).
While an effort is made to continuously improve the overall quality and consistency of the MGEX data in cooperation with all providers, the MGEX project relies on volunteers and can't commit on fixing all problems on short notice. However, the feedback of all users is appreciated to document known issues and to share this infomarmation within the MGEX community.
Real-time data streams for a large fraction of MGEX stations are publicly available at the MGEX NTRIP caster of BKG. Information on accessing (or contributing) MGEX real-time streams is provided on the MGEX Real-time Streaming FAQ page of BKG.
Last Updated: 2017/01/23 15:46:38