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Global Differential GPS System
About Us
System Description
- Overview
- Network
- Software
- References
Live Performance Monitoring
Customer Portal
Global Virtual Reference Network

We can translate our globally-uniform GPS orbit and clock corrections as well as our real-time global ionospheric map into RTCM 104 formatted corrections from a virtual reference site anywhere in the world. In other words, if your augmentation or A-GPS service is based on local differential corrections we can mimic these type of corrections with our global system. Uniquely, we also fold in local corrections of tropshperic delay using near-real-time weather fields, and take into account the local topography. The resulting differential corrections enable single-frequency users anywhere in the world to derive positioning nearly as accurately as dual-frequency users.

It does not matter where you need the service. We'll save you the cost of deploying reference receivers. Our virtual reference site is already there, and optimally positioned for your customers. We'll be happy to accommodate any message format you need.

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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