| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a vehicle-mounted receiver with a constitution for improving a noise-resistant performance of wireless signals from a mobile device without misoperations such as receipt of tire air pressure monitoring electric waves of other vehicles when other vehicles pass near one's own parked vehicle, judging frequency of signals received at a common antenna according to an on/off condition of an engine, and demodulating the signals from the mobile device and a transmitter/receiver by a demodulating part corresponding in modulating system, because a modulating system of the mobile device for keyless entry can be differentiated from a modulation system of the transmitter/receiver for monitoring the tire air pressure. <P>SOLUTION: This vehicle-mounted receiver 13 receives wireless signals from a mobile device 13 for keyless entry held by a user and wireless signals from TPMS transmitters/receivers 12A-12D for monitoring the air pressure of the tires mounted to a vehicle C. This receiver comprises a common antenna part 24 receiving wireless signals modulated and transmitted in an ASK modulation system from the TPMS transmitters/receivers 12A-12D, an FSK demodulation part 32 demodulating the signals received by the common antenna part 24 according to the FSK modulation system at the time of stopping the engine, and an ASK demodulation part 33 demodulating the signals received by the common antenna part 24 according to the ASK modulation system at the time of starting the engine. <P>COPYRIGHT: (C)2006,JPO&NCIPI</p> |
