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Global Differential GPS System
About Us
System Description
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The Global Differential GPS (GDGPS) System is a complete, highly accurate, and extremely robust real-time GPS monitoring and augmentation system.

Employing a large ground network of real-time reference receivers, innovative network architecture, and award-winning real-time data processing software, the GDGPS System provides decimeter (10 cm) positioning accuracy and sub-nanosecond time transfer accuracy anywhere in the world, on the ground, in the air, and in space, independent of local infrastructure.

A complete array of real-time GPS state information, environmental data, and ancillary products are available in support of the most demanding GPS Augmentation operations, Assisted GPS (A-GPS) services, situational assessment, and environmental monitoring - globally, uniformly, accurately, and reliably.

Autonomous Ephemeris Prediction (AEP) software
No Connectivity? - No Problem
Now offering a complete product line of real-time GLONASS data:
GREAT ALERT - Real-Time Precise Point Positioning Services for Natural Hazard Prediction and Monitoring
The Largest Real-time Tracking Network
Global map
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 GPS Data
- Assisted GLONASS Data
- GLONASS corrections, orbit and clocks

- Automatic Precise Positioning Service
- Consulting
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