Method and device for protecting a motor vehicle
US7545254B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Nov 15, 2005 |
| Grant date | Jun 9, 2009 |
| Priority date | — |
| Expiry date | Jul 5, 2027 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG07C2209/63
- WIPO fieldControl
- WIPO sectorInstruments
Abstract
In a method for protecting a motor vehicle, the vehicle is equipped with antennas such that each zone of the cabin is covered by at least two antennas, and with an electronic tag furnished with a device measuring three-dimensional orientation of the magnetic fields received by the electronic tag. A sequence of emissions that consists of a succession of magnetic fields emitted in succession in a given random order from the antennas of the vehicle is randomly determined. After the tag receives this magnetic field succession, a check is carried out to verify that the random emission order has indeed been complied with and that the orientation of the fields that is received by the tag conforms to the expected random orientation. Additionally, the amplitude of the fields can be randomly varied. Authorization to start the vehicle is granted if this random variation is actually received by the tag.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.