Electronic license plate communication system, electronic license plate communication method, and electronic license plate used therefor

摘要

PPROBLEM TO BE SOLVED: To enhance the lifetime of the power supply for an electronic license plate. PSOLUTION: The electronic license plate 3 is arranged no to be actuated when a vehicle stops in the communication area of an electronic license plate communication unit 2. More specifically, a wake up circuit 3b and a wake up control circuit 3c are provided and the electronic license plate 3 can be supplied with power from a battery 3e when a radio wave from the electronic license plate communication unit 2 received at a radio communication section 3a is not lower than a specified voltage level, but power is not supplied when the radio wave is lower than the specified voltage level. Since power consumption of the battery 3e can be reduced, lifetime of the battery 3e can be enhanced. PCOPYRIGHT: (C)2005,JPO&NCIPI