Keyless entry system, and system transmitter having optimized signal transmission power level
US6292107A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 27, 1998 |
| Grant date | Sep 18, 2001 |
| Priority date | — |
| Expiry date | Aug 27, 2018 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG07C2009/00793
- WIPO fieldControl
- WIPO sectorInstruments
Abstract
A keyless entry system transmitter that achieves both a reduction in power consumption when transmitting radio signals, and enhances system convenience by boosting transmission power in cases where required. A set-voltage value corresponding to a function specified by operation of an operation switch is read from a corresponding-voltage memory portion, and this read set-voltage value is output to a DAC. Accordingly, when operation specifying the same function is again performed with the operation switch before a predetermined timeout time clocked by a timer has elapsed, a counter is incremented, and a voltage-setting output to the DAC increases in accordance with a count value thereof. As a result, voltage supplied to a transmitter unit through a regulator increases as well. Consequently, transmission power of a remote-control signal sent via a transmission antenna is also increased.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.