| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To immediately detect that failure occurs when wireless communication is not executed by a fault or the like of a wireless communication means of an ETC system. <P>SOLUTION: A checking on-vehicle device 110 installed in a communication area 108 of an antenna 107 periodically starts, and executes the wireless communication with the antennas 107. When receiving a response of the checking on-vehicle device 110 through the antenna 107, a controller 109 decides that the wireless communication means of the antenna 107 is in the middle of normal operation. When not receiving the response of the checking on-vehicle device 110 through the antenna 107 even if timing when the checking on-vehicle device 110 starts lapses, it is decided that the communication means of the antenna 107 is in an abnormal state. <P>COPYRIGHT: (C)2008,JPO&INPIT</p> |
