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Global Differential GPS System
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Integrity & Performance Monitoring

From monitoring the integrity of the GPS constellation, to situational awareness for theaters of operation, to the support of critical operations world-wide, JPL has the unrivalled ability to assess the performance of the GPS navigation signals in real-time.

JPL operates the only global ground network that is capable of inferring the satellite state in real time globally, and to separate clock performance from orbit performance. JPL's network tracks each GPS satellite with at least 10 tracking stations simultaneously and, on average, with 25 tracking stations. The dense tracking network also provides extraordinary level of redundancy and the opportunity for strong majority voting schemes.

Our suite of monitoring tools provides customized alarm thresholds with as little as 4 seconds time to alarm, graphical and binary user interfaces, communications protocols, and around-the-clock operations for the most demanding applications. The GDGPS staff of engineers can tailor a performance monitoring application for your needs.

Access to some of the integrity monitoring information may require approval by the Department of Defense.

JPL GPS Integrity Monitor map
Snapshot from the JPL GPS Integrity Monitor web page (restricted access), depicting links between the GPS satellites and the ground tracking sites.

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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