MGEX Data & Products
MGEX Data Holdings
The Multi-GNSS Pilot Project (MGEX) has been set-up by the IGS to track, collate and analyze all available GNSS signals. This includes signals from BeiDou, Galileo, QZSS, and IRNSS, 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.
Recent observation data of IGS Multi-GNSS stations in RINEX3 format are available from the IGS global data centers
- Crustal Dynamics Data Information System (CDDIS)
- Institut Géographique National (IGN)
- Bundesamt für Kartographie und Geodäsie (BKG)
The RINEX 3 file names comprise a 9-char station+country/region 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 RINEX 3 gzipped daily, Hatanaka compressed observation file with 30-s sampling for the IGS MAS1 station in Spain. A detailed specification of the new file naming scheme is provided as part of the RINEX3 Standard. RINEX 2 files that reside in the same directory follow the old “8.3” naming scheme, e.g., mas12350.14d.Z. The archives provide daily RINEX files at 30 s update rate as well as high-rate (1 Hz) files for selected stations. 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.
Historic Data
Provision of MGEX observation data started with dedicated MGEX project directories at the global data centers. In the frame of the RINEX transition plan the IGS pursued the integration of multi-GNSS observation and navigation data in RINEX3 format and RINEX2 data from legacy stations in 2015/2016. Historic MGEX observation files back to 2012 and for individual stations and days even back to 2010 are available from
Notes
MGEX 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.
Furthermore, different generation methods may apply for daily and high-rate data files. Depending on the employed tool chain and software revisions, various deficiencies have occurred that affect past and/or current data in the MGEX archive. Users cannot presently expect full consistency of all data and literal adherence to the RINEX3 standard. Known problems include
- Inconsistency 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).
In addition, receiver-specific problems may result in a degraded measurement quality for some of the new signals and constellations.
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 information within the MGEX community.
Real-Time Data
Real-time data streams for dedicated multi-GNSS stations are publicly available at the MGEX NTRIP caster of BKG. In addition, many stations of the regular IGS real-time service support multi-GNSS observations.
NETWORK
The current status of the global multi-GNSS network is shown on the IGS Network page along with supporting information from the site database.
Precise Orbit and Clock Products
Orbit and clock products that become available as part of the MGEX data analysis are made available at the CDDIS MGEX product archive (Earthdata login required) as well as mirror sites hosted by IGN and ENSG. The products are stored in weekly directories (identified by the 4-digit GPS week) and identified by a three letter analysis center ID identifying the contributing agency. Seven MGEX analysis centers are presently contributing dedicated multi-GNSS products for MGEX on a routine basis:
- Centre National d’Etudes Spatiales (CNES), Collecte Localisation Satellites (CLS), Groupe de Recherche de Géodésie Spatiale (GRGS)
- Center for Orbit Determination in Europe (CODE)
- GeoForschungsZentrum Potsdam (GFZ)
- Information and Analysis Center (IAC)
- Japan Aerospace Exploration Agency (JAXA)
- Shanghai Observatory (SHAO)
- Wuhan University
First orbit and clock products for selected new constellations were provided by the MGEX Analysis Centers (ACs) in mid 2012 (GPS week 1680). Since then an increasing number of multi-constellation products covering up to five global or regional navigation satellite systems has become available. In addition to precise ephemerides, clock products with sampling intervals down to 30 s, attitude quaternions, Earth orientation parameters (EOPs), and biases are generated by individual ACs. Selected ACs also provide station coordinates and EOPs in the Solution INdependent EXchange (SINEX) format. An overview of products available as of February 2024 is provided in the following table.
|
Institution
|
ID
|
Constellations
|
Products
|
References
|
Analysis log
|
|---|---|---|---|---|---|
| CNES/CLS | GRG0MGXFIN | GPS+GLO+GAL | Satellite orbits and clocks (15 min; *.SP3) Satellite and station clocks (30 s; *.CLK) Attitude (30 s; *.OBX) Site coordinates and EOPs (*.SNX) Biases (1 d; *.BIA) |
Loyer et al. (2018) | GRG0MGXFIN.acn |
| CODE | COD0MGXFIN | GPS+GLO+GAL +BDS2+BDS-3+QZS | Satellite orbits and clocks (5 min; *.SP3) Satellite and station clocks (30 s/5 min; *.CLK) Attitude (30 s; *.OBX) Earth orientation parameters (12 h; *.ERP) Biases (1 d; *.BIA) |
Prange et al. (2020a), Prange et al. (2020b) |
|
| GFZ | GFZ0MGXRAP | GPS+GLO+GAL +BDS2+BDS-3+QZS | Satellite orbits and clocks (15 min; *.SP3) Satellite and station clocks (30 s/5 min; *.CLK) Attitude (30 s; *.OBX) Earth orientation parameters (1 d; *.ERP) Biases (1 d; *.BIA) |
IGSMAIL-7748, GFZ MGEX website |
GFZ0MGXFIN.acn |
| IAC | IAC0MGXFIN | GPS+GLO+GAL +BDS2+BDS3+QZS | Satellite orbits and clocks (5 min; *.SP3) Satellite and station clocks (30 s; *.CLK) |
IAC0MGXFIN.acn | |
| JAXA | JAX0MGXFIN | GPS+GLO+QZS | Satellite orbits and clocks (5 min; *.SP3) Satellite and station clocks (30 s; *.CLK) Earth orientation parameters (1 d; *.ERP) Site coordinates and ERPs (*.SNX) |
JAX0MGXFIN.acn | |
| SHAO | SHA0MGXRAP SHA0MGXULT |
GPS+GLO+GAL +BDS2+BDS-3 | Satellite orbits and clocks (15 min; *.SP3) Satellite and station clocks (5 min; *.CLK) Earth orientation parameters (1 d; *.ERP) |
||
| Wuhan Univ. | WUM0MGXFIN WUMMGXRAP WUMMGXULT |
GPS+GLO+GAL +BDS2+BDS3+QZS | Satellite orbits and clocks (15 min; *.SP3) Satellite and station clocks (5 min; *.CLK) Attitude (30 s; *.OBX) Earth orientation parameters (1 d; *.ERP) Biases (1 d; *.BIA) |
WUM0MGXFIN.acn WUM0MGXRAP.acn |
Discontinued and former products are listed below:
|
Institution
|
ID
|
Availability
|
References
|
|---|---|---|---|
| CNES/CLS | grm | until week 2024 | Loyer et al. (2016) |
| CODE | com | until week 1961 | Prange et al. (2015), Prange et al. (2016) |
| GFZ | gfm | until week 1789 | Uhlemann and Fritsche (2014) |
| GFZ | gbm | until week 2037 | Deng et al. (2014), Uhlemann et al. (2015) |
| JAXA | qzf | until week 1938 | |
| TUM | tum | until week 2024 | |
| TUM | TUM0MGXRAP | until 314/2019 | Selmke et al. (2018) |
| Wuhan Univ. | wum | until week 2033 | Guo et al. (2016) |
Broadcast Ephemerides
In addition to the aforementioned precise orbit and clock products, combined multi-GNSS broadcast ephemeris files are made available by Bundesamt für Kartographie und Geodäsie (BKG), Institut Géographique National (IGN), IGS, and Deutsches Zentrum für Luft- und Raumfahrt (DLR).
| Institution | File name | Constellations | Notes |
|---|---|---|---|
| BKG | BRDC00WRD_S_yyyydddhhmm_01D_MN.rnx.gz | GPS+GLO+GAL+BDS+QZSS+SBAS | Converted from stream RTCM3EPH on http://mgex.igs-ip.net |
| IGN | BRDC00IGN_R_yyyydddhhmm_01D_MN.rnx.gz | GPS+GLO+GAL | also files for GPS-only (GN), GLONASS-only (RN) and Galileo-only (EN) |
| IGS | BRDC00IGS_R_yyyydddhhmm_01D_MN.rnx.gz | GPS+GLO+GAL+BDS +QZSS+SBAS |
Merged from receiver-generated RINEX navigation files |
| DLR | brdmdddn.yyp.Z | GPS+GLO+GAL+BDS +QZSS+IRNSS+SBAS |
Merged from streams of about 35 stations, until Jan/2020 |
| DLR | BRDM00DLR_S_yyyyddd0000_01D_MN.rnx.gz | GPS+GLO+GAL+BDS +QZSS+IRNSS+SBAS |
Merged from streams of about 35 stations, since 329/2019 |
The various broadcast ephemerides are provided in the form of RINEX3 navigation files:
- The BRDM00DLR and BRDX00DLR product files are available in the annual archives of the CDDIS and the daily archives of IGN and BKG.
- The IGN BRDC product is available in the daily data archives at IGN.
- The IGS BRDC product is available in the annual data archives of CDDIS and the daily data archives at IGN.
- BKG’s product can independently be obtained from the BKG BRDC archive, which also provides near-real-time version updated at 15 min intervals in a sliding window mode.
As a special product, MGEX offers daily sets of GPS CNAV data recorded from a global subset of MGEX stations. Details of the contents and format are provided in the CNAV section of the MGEX GPS status page.
Real-Time Products
Complementary to the multi-GNSS observation data provided in the real-time streams of individual MGEX stations, a distinct broadcast ephemeris stream (RTCM3EPH) is made available at the IGS-IP products caster. The stream is combined from a broadcast ephemerides delivered by a globally distributed set of stations and covers the complete GPS, GLONASS and Galileo constellation. For further information and alternative broadcast ephemeris streams users are referred to the BKG web page on Broadcast Ephemeris from EUREF & IGS Real-time GNSS Resources.
Differential Code Biases
Proper knowledge of differential code biases (DCBs) is essential in many navigation applications but also non-navigation applications such as ionospheric analysis and time transfer. With the plethora of new signals offered by modernized and new GNSSs, the need for a comprehensive multi-GNSS DCB product arises.
As part of the IGS Multi-GNSS Experiment (MGEX) three different DCB products are presently provided by the Aerospace Information Research Institute (AIR) of the Chinese Academy of Sciences (CAS), the German Aerospace Center (DLR), and the German Research Center for Geosciences (GFZ) at the CDDIS and IGN product archives:
| Institution | Products | Constellations and Signals | Notes |
|---|---|---|---|
| CAS | CAS0MGXRAP_yyyyddd0000_01D_01D_DCB.BSX.gz CAS0MGXRAP_yyyyddd0000_01D_01D_OSB.BIA.gz CAS1MGXRAP_yyyyddd0000_01D_01D_DCB.BSX.gz CAS1MGXRAP_yyyyddd0000_01D_01D_OSB.BIA.gz |
GPS(C1C,C1W,C2L/S/X,C2W,C5Q/X) GLO(C1C,C1P,C2C,C2P) GAL(C1C/X,C5Q/X,C6C,C7Q/X,C8Q/X) BDS(C1X,C2I,C5D/P/X,C6I,C7I/Z,C8X) QZS(C1C/X,C2L/X,C5Q/X) |
Wang et al. (2016) |
| DLR | DLR0MGXFIN_yyyyddd0000_03L_07D_DCB.BSX.gz DLR0MGXFIN_yyyyddd0000_03L_01D_DCB.BSX.gz |
GPS(C1C,C1W,C2L/S/X,C2W,C5Q/X) GPS(C1L,C1X) since Mar/2020 GLO(C1C,C1P,C2C,C2P) GAL(C1C/X,C5Q/X,C7Q/X,C8Q/X) GAL(C6C) since Q2/2017 BDS(C2I,C6I,C7I) BDS(C5X) since Jan/2019 BDS(C1X) since Mar/2019 BDS(C7Z) since Aug/2019 BDS(C1P,C5P) since Q4/2021 QZS(C1C/X,C2L/S/X,C5Q/X) since Q3/2017 |
Montenbruck et al. (2014) |
| GFZ | GFZ0MGXRAP_yyyyddd0000_01D_01D_DCB.BSX.gz | GPS(C1W,C2W) GAL(C1C,C5Q) BDS(C2I,C6I) QZS(C1C,C2C) |
Brack et al. (2021) |
The CAS and DLR DCB products offer continuous data since Jan. 1, 2013 but differ in the coverage and update rate. These DCBs are derived from ionosphere-corrected pseudorange differences and cover signals of GPS, GLONASS, Galileo, BeiDou, and QZSS. The satellite and station biases computed by the CAS are generated on a daily basis with a latency of 2-3 days and made available in daily Bias SINEX files. Going back to 2017, these products are also available as observation-specific code biases (OSBs). Starting with 172/2022, CAS also provides an OSB and DCB product considering satellite phase center offset (PCO) corrections. This product labeled CAS1MGXRAP is only available at the CAS ftp server ftp.gipp.org.cn/product/dcb/mgex/. More details can be found in Wang et al. (2022).
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. Note that station DCBs are not required in common positioning applications where they will typically be absorbed in clock offsets or inter-system biases.
Starting with the IGS switch to IGS20/igs20.atx on 27 November 2022 (day of year 331/2022), the DLR product considers the phase center corrections for DCB estimation. Due this model change, two separate sets of DCB files are provided for the 4th quarter of 2022:
- DLR0MGXFIN_20222740000_02L_07D_DCB.BSX.gz and DLR0MGXFIN_20222740000_02L_01D_DCB.BSX.gz covering 1 October until 26 November without PCO corrections
- DLR0MGXFIN_20223310000_01L_07D_DCB.BSX.gz and DLR0MGXFIN_20223310000_01L_01D_DCB.BSX.gz covering 27 November until 31 December with PCO corrections
GFZ started to provide a rapid DCB product on 27 November 2022 (day of year 331/2022). This product considers the phase center corrections for DCB estimation from the very beginning. It is a byproduct from the estimation of global ionosphere maps.
Transition to operational products
Recognizing their maturity and aiming at a comprehensive integration of multi-GNSS products into the standard service product portfolio, the IGS has decided to treat the multi-GNSS DCB products as fully operational products. This decision implies that the campaign/project identifier in file names will be changed from “MGX” to “OPS” and the file extension will be changed from “BSX” to “BIA” in accord with the Guidelines for Long File Names in the IGS.
The switch is scheduled to take place on January 23, 2024. From this date onwards, all multi-GNSS DCB product will be delivered with the revised names. For a transition period of about one month, products with old and new file names are provided. Furthermore, the existing multi-GNSS DCB product holdings at the data centers will be renamed to match the new convention back to GPS week 2237 (= 2022/11/20 = DOY 324 of 2022; marking the introduction of IGS20).
| Institution | Products | Constellations and Signals | Notes |
|---|---|---|---|
| CAS | CAS0OPSRAP_yyyyddd0000_01D_01D_DCB.BIA.gz CAS0OPSRAP_yyyyddd0000_01D_01D_OSB.BIA.gz CAS1OPSRAP_yyyyddd0000_01D_01D_DCB.BIA.gz CAS1OPSRAP_yyyyddd0000_01D_01D_OSB.BIA.gz |
GPS(C1C,C1W,C2L/S/X,C2W,C5Q/X) GLO(C1C,C1P,C2C,C2P) GAL(C1C/X,C5Q/X,C6C,C7Q/X,C8Q/X) BDS(C1X,C2I,C5D/P/X,C6I,C7I/Z,C8X) QZS(C1C/X,C2L/X,C5Q/X) |
Wang et al. (2016) |
| DLR | DLR0OPSFIN_yyyyddd0000_03L_07D_DCB.BIA.gz DLR0MGXFIN_yyyyddd0000_03L_01D_DCB.BIA.gz |
GPS(C1C,C1L/W/X,C2L/S/W/X,C5Q/X) GLO(C1C,C1P,C2C,C2P) GAL(C1C/X,C5Q/X,C6C,C7Q/X,C8Q/X) BDS(C2I,C1P/X,C5P/X,C6I,C7I/Z) QZS(C1C/X,C2L/S/X,C5Q/X) |
Montenbruck et al. (2014) |
| GFZ | GFZ0OPSRAP_yyyyddd0000_01D_01D_DCB.BIA.gz | GPS(C1W,C2W) GAL(C1C,C5Q) BDS(C2I,C6I) QZS(C1C,C2C) |
Brack et al. (2021) |
Operational product availability
Last Updated on 28 Feb 2024 06:55 UTC