Roadside beacon system
US4896161A · kind A · utility
2Cited by
3References
5Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Jun 18, 1987 |
| Grant date | Jan 23, 1990 |
| Priority date | — |
| Expiry date | Jun 18, 2007 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG08G1/13
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A navigator system for providing in a moving vehicle a display of the position of the vehicle on a map. This position is recalibrated by a roadside antenna that transmits a split beam so that the signal is a minimum directly in front of the antenna. The on-board navigator recalibrates the position from data transmitted immediately before when the received signal is abruptly decreased as the vehicle passes directly in front of the antenna.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.