| 摘要 |
<p>The present invention provides a passive keyless entry device which is capable of adjusting a level of transmitting signal of a vehicle-mounted transceiver 14 in correspondence to a variation of the state of arrangement of the vehicle-mounted transceiver 14 with a portable transceiver 1. The portable transceiver 1 comprises a receiving antenna 7 for receiving the wakeup signal, a signal receiver 3 including a signal detector 3D for processing a signal received from the receiving antenna, a signal level discriminator 4 for determining whether a level of the signal received from the receiving antenna exceeds an input tolerance limit of the signal detector 3D, a controller 5, and a signal transmitter 6 for transmitting a signal to the vehicle-mounted transceiver, the controller 5 transmits a request signal to the vehicle-mounted transceiver via the signal transmitter 6 when the signal level discriminator 4 determines that the level of the signal received from the receiving antenna exceeds the input tolerance limit of the signal detector 3D, and the vehicle-mounted transceiver again transmits the wakeup signal to the portable transceiver 1, with a signal level lowered by a certain level, upon receiving the request signal. <IMAGE></p> |
