Start-up method for mobile transceivers, mobile transceivers and fixed transceivers thereof
US5682603A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jul 19, 1995 |
| Grant date | Oct 28, 1997 |
| Priority date | — |
| Expiry date | Jul 19, 2015 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG08G1/017
- WIPO fieldControl
- WIPO sectorInstruments
Abstract
To provide a communications system to accurately detect when a mobile transceiver has entered an area where communication with a fixed transceiver is possible, and to start-up the internal circuitry of the mobile transceiver, a communications system transmits a start-up pilot signal of a prescribed period from a transponder mounted in a fixed station to a transponder mounted in a vehicle. In the transponder, the received signal upon being received by an antenna is detected in a detector and amplified in an amplifier. When this signal is greater than a reference voltage, a pulse is output from a level discriminator. This pulse signal is converted into a pulse of constant pulse width in a discriminator pulse generator and integrated in an integrator. When the integrated value exceeds a reference voltage, a start-up discriminator sends a drive signal to actuate the internal circuitry of the mobile transceiver. As a consequence, mistaken start-up of the internal circuitry due to noise input is prevented and the internal circuitry is started only when necessary.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.