| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a passive keyless entry system which can prolong the long of a battery of a portable machine while suppressing a deterioration in performance, when communication is performed with a predetermined time period between a vehicle-side device and the portable machine. <P>SOLUTION: This passive keyless entry system is equipped with a control portion 10 which transmits a request signal with a predetermined time period from the vehicle-side device 2, which transmits an answer signal when the portable machine 5 receives the request signal, and which performs predetermined control when the vehicle-side device 2 receives or does not receive the answer signal. The portable machine is equipped with a portable-machine control portion 20 which detects the intensity of the request signal transmitted from the vehicle-side device. The portable-machine control portion transmits a normal response signal as the answer signal when the intensity of the request signal is changed by a predetermined value or above, in comparison with the intensity of the request signal received before then, and transmits a simple response signal, shorter than the normal response signal, as the answer signal when the intensity of the request signal is changed by less than the predetermined value. <P>COPYRIGHT: (C)2008,JPO&INPIT</p> |
