发明名称 Anti-theft system for a motor vehicle
摘要 A transceiver with an antenna oscillating circuit generates a magnetic field which inductively charges a charge capacitor of a transponder through a transponder oscillating circuit. A frequency-modulated oscillation is thereupon generated in the transponder and that oscillation is transmitted back to the transceiver. In order to ensure that the transceiver will receive the highest possible amplitudes of the frequency-modulated oscillation, the resonant frequency of the antenna oscillating circuit is adapted to the oscillation frequencies of the transponder oscillating circuit. To that end, an impedance is connected, automatically weighted, to the antenna oscillating circuit.
申请公布号 US5905444(A) 申请公布日期 1999.05.18
申请号 US19960745499 申请日期 1996.11.12
申请人 SIEMENS AKTIENGESELLSCHAFT 发明人 ZIMMER, HERBERT
分类号 B60R25/00;B60R25/20;B60R25/40;G07C9/00;(IPC1-7):H04Q1/00 主分类号 B60R25/00
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