| 摘要 |
PURPOSE:To surely prevent illegal act caused by intercept of a radio wave signal from a remote key through the reception synchronously with a transmission signal from the remote key with simple configuration. CONSTITUTION:Every time an operation button of a remote key is operated, a transmission circuit sends a count code (p) and an ID code C (k) corresponding thereto as a radio wave signal. The count code is set corresponding to N sets of different ID codes to form a code signal. A receiver of a vehicle body stores similar code signals in its memory 37 and reads the received count code (p) and the designated count code P from the memory 37 upon the receipt of the code signal and reads the ID code corresponding to the received count code (p) in the case of count value k>=K for the collation and provides an output of matching detection signal when they are matched and resets the designated count code into the original count code P in the case of dismatching. Even when the code signal is intercepted illicitly, since the receiver does not accept the signal when the corresponding ID code is not set together with the advancement of the count code (p), the security is improved. |
