首页>
外国专利>
Transponder excitation unit of e.g. passive start and entry system for e.g. motor vehicle, has signal source that changes oscillator signal provided to antenna depending on undervoltage signal
Transponder excitation unit of e.g. passive start and entry system for e.g. motor vehicle, has signal source that changes oscillator signal provided to antenna depending on undervoltage signal
The transponder excitation unit has an antenna for generating an electromagnetic field dependent upon an oscillator signal. A signal source is adapted to generate the oscillator signal and to supply the voltage to the antenna. A detector circuit detects if the supply voltage falls below threshold so as to produce undervoltage signal. The signal source changes the oscillator signal depending on the undervoltage signal. Independent claims are included for the following: (1) access and start system for vehicle; and (2) method for enabling communication between transponder excitation unit and transponder.
展开▼
