Position and velocity estimation system for adaptive weighting of GPS and dead-reckoning information
US5416712A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 28, 1993 |
| Grant date | May 16, 1995 |
| Priority date | — |
| Expiry date | May 28, 2013 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01S19/52
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
An embodiment of the present invention is a combined GPS and dead-reckoning (DR) navigation sensor for a vehicle in which a pair of modifications are made to an otherwise conventional Kalman filter. Process noise is adapted to cope with scale factor errors associated with odometer and turning rate sensors, and correlated measurement error processing is added. When only two Doppler measurements (PRRs), or three with an awkward three-satellite geometry, are available, DR error growth can nevertheless be controlled. The measurement error correlations in the conventional Kalman filter covariance propagation and update equations are explicitly accounted for. Errors induced by selective availability periods are minimized by these two modifications.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.