Method and apparatus for autonomous, in-receiver prediction of GNSS ephemerides
US8120529B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 11, 2008 |
| Grant date | Feb 21, 2012 |
| Priority date | — |
| Expiry date | Jun 9, 2030 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01S19/27
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
Methods and apparatus for autonomous in-receiver prediction of orbit and clock states of Global Navigation Satellite Systems (GNSS) are described. Only the GNSS broadcast message is used, without need for periodic externally-communicated information. Earth orientation information is extracted from the GNSS broadcast ephemeris. With the accurate estimation of the Earth orientation parameters it is possible to propagate the best-fit GNSS orbits forward in time in an inertial reference frame. Using the estimated Earth orientation parameters, the predicted orbits are then transformed into Earth-Centered-Earth-Fixed (ECEF) coordinates to be used to assist the GNSS receiver in the acquision of the signals. GNSS satellite clock states are also extracted from the broadcast ephemeris and a parameterized model of clock behavior is fit to that data. The estimated modeled clocks are then propagated forward in time to enable, together with the predicted orbits, quicker GNSS signal acquision.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.