Door entry control by wireless communication
US6218929A · kind A · utility
Assignees
Inventors
Key dates
| Filing date | Jun 10, 1998 |
| Grant date | Apr 17, 2001 |
| Priority date | — |
| Expiry date | Jun 10, 2018 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG07C2009/00793
- WIPO fieldControl
- WIPO sectorInstruments
Abstract
In a vehicular entry control system, a code signal transmitter of a card carried by a driver modulates by a card-specific code a signal received from a transmitter/receiver of a control unit mounted in a vehicle and transmits the modulated signal to the control unit in return. The transmitter/receiver demodulates the modulated signal and a microcomputer automatically unlocks a vehicle door when the demodulated signal is correct indicating that the card is carried into a demodulating area. The microcomputer locks the door upon a driver's manual operation on a locking switch of the card. The microcomputer prohibits the automatic unlocking as long as the card is within the demodulating area after the locking in response to the manual operation.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.