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Embedded Autonomous Ephemeris Prediction (AEP) software

Embedded GPS/GLONASS Autonomous Ephemeris Prediction (AEP) software enables fast signal acquisition in your PND or cell phone without any external aiding whatsoever. No Connectivity - No Problem!

AEP is a compact software designed to reside inside the PDA/cell phone. The software uses infrequent and intermittent snapshots of the GPS (and GLONASS) broadcast ephemeris, taken by the embedded GPS chipset, to infer the orbit and clock states of the GNSS constellation and accurately predict it forward for many days. AEP does not use any externally-supplied information whatsoever. AEP uses an innovative approach to overcome the critical unknowns impacting the autonomous orbit prediction process, and employs JPL's sophisticated satellite dynamics models for the highest possible accuracy. AEP predicts the GNSS orbit and clock states nearly as well as JPL's network-based AGPS product. Actual Time to First Fix (TTFF) improvements depend upon the GNSS chipset performance.

AEP is written in highly portable C. It has been ported to Linux, and Windows Mobile in a variety of host platforms. JPL will work with your company to tailor the software and its interface to your specific operational environment, and your specific requirements.

Key specifications:

  • Load size: 400 KB
  • Typical 7th-day orbit and clock prediction accuracy (median over all satellites): 15 m User Range Error (URE)
  • Typical 28th-day orbit and clock prediction accuracy (median over all satellites): 150 m User Range Error (URE)

AEP is an intellectual property of the California Institute of Technology. For more information please contact Dr. Yoaz Bar-Sever

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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