Method of producing rolling code and keyless entry apparatus using the same
US6225889A · kind A · utility
13Cited by
7References
13Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Dec 24, 1996 |
| Grant date | May 1, 2001 |
| Priority date | — |
| Expiry date | Dec 24, 2016 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG07C2009/00492
- WIPO fieldControl
- WIPO sectorInstruments
Abstract
A rolling code producing method is provided which may be employed in a keyless entry system for automotive vehicles designed to compare a rolling code derived in a receiver installed in the vehicle and a rolling code derived in a portable transmitter to allow authorized access to the vehicle if both the rolling codes match. The rolling code producing method includes producing different rolling codes, in sequence, using an initial code variable according to a given algorithm and changing the initial code variable in response to insertion of an initial code variable memory card carried by a vehicle operator into the receiver.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.