Combined relative and absolute positioning method and apparatus
US5311195A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 30, 1991 |
| Grant date | May 10, 1994 |
| Priority date | — |
| Expiry date | Aug 30, 2011 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01S19/49
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A navigation system comprising a relative positioning system (RPS) with dead reckoning and map matching and an absolute positioning system (APS) is provided and operated in such a manner that APS position information is used for updating RPS position and contour of equal probability (CEP) information as required. The APS may comprise a Loran-C or a global positioning system (GPS). Different criteria are used for resetting the RPS depending on whether or not the navigation system comprises a Loran-C or a GPS due to the different levels of precision of the Loran-C and the GPS. When the RPS is reset or updated, it is updated to the current APS position with its offset, if any. Its contour of equal probability (CEP) may also be adjusted.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.