Method for improving vehicle positioning in a navigation system
US6597987B1 · kind B1 · utility
Assignee
Inventor
Key dates
| Filing date | May 15, 2001 |
| Grant date | Jul 22, 2003 |
| Priority date | — |
| Expiry date | Jul 20, 2021 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01S19/47
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A method implemented on a navigation system in a vehicle for determining the position of the vehicle relative to a road network. The navigation system uses a geographic database that contains data that represent positions of roads upon which the vehicle travels. Using the output from a GPS system, and optionally outputs from other sensors, the navigation system matches the positions of the vehicle to the locations of the roads represented by the data contained in the geographic database. Upon detecting an event from which the position of the vehicle with respect to the roads represented by the data contained in the geographic database can be determined with a relatively high degree of accuracy, a correction factor is determined. The correction factor is an offset (i.e., a distance and direction) of the GPS position reported during the event to the known-to-be-highly-accurate position. The correction factor is then used to adjust subsequently obtained GPS readings for a limited period of time, i.e., while the same atmospheric conditions apply. This period of time may be 10-20 minutes.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.