GPS/self-contained combination type navigation system
US4903212A · kind A · utility
Assignees
Inventors
Key dates
| Filing date | Mar 11, 1988 |
| Grant date | Feb 20, 1990 |
| Priority date | — |
| Expiry date | Mar 11, 2008 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01C21/28
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
In a global positioning system (GPS)/self-contained combination type navigation system for a vehicle, the GPS navigation data are received by the GPS antenna of the navigation system which are simultaneously transmitted from more than 3 pieces of satellites inclusively. From the GPS navigation data, GPS type velocity data is calculated, whereas self-contained type velocity data is calculated from self-contained type navigation data such as azimuth data and drive-distance data of the vehicle. Only when a difference between the self-contained type velocity data and the GPS type velocity data exceeds a threshold velocity, the GPS type velocity data is voided so as to determine the present position of the vehicle.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.