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Global Differential GPS System
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Broadcast Ephemeris & Almanac

We distill the GNSS broadcast ephemerides and almanacs from the navigation message received by our vast ground network, weeding out bit errors and data errors with strong majority voting schemes.

For GPS, Both the broadcast ephemerides and the broadcast almanacs for each satellite are available in a RINEX-like file format. We include the "Klobuchar" ionosphere correction parameters in the broadcast ephemeris files. The full resolution broadcast ephemerides are also available in a streaming socket format.

For non-GPS GNSS, we provide the broadcast ephemeris in RINEX format.

Additional broadcast parameters needed for some A-GPS protocols, but that are not part of the RINEX standard, are provided in a separate 'delta' file. We also embed in these 'delta' files real-time URE performance metrics from the GDGPS orbit determination process, for actual, up to the minute satellite performance status.

The RINEX broadcast ephemeris files are updated every 5 minutes. The ephemeris 'delta' files are updated every minute. The almanac files are updated every 12.5 minutes. The broadcast ephemeris (with the parameters of the RINEX file) is also available as a continuous UDP data stream.

Access to all these products is available concurrently from multiple redundant data centers for optimal reliability.

Real-time GNSS
Products & Services
Precise, Global, Reliable
- Embedded Autonomous Ephemeris Prediction (AEP) software
- Orbit & Clock Corrections
- Orbit & Clock States
- Broadcast Ephemeris & Almanac
- Complete 50 bps Navigation Message
- Global Ionospheric (TEC) Maps
- Raw Measurements
- Predicted Orbit & Clock States
- Integrity & Performance Monitoring
- Global Virtual Reference Network
- Assisted GNSS Data
- GLONASS corrections, orbit and clocks

- Automatic Precise Positioning Service
- Consulting
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