ID PLATE

PURPOSE:To check an ID number and to prevent a vehicle from illegally entering into a specific area by storing the ID number inherent in each plate and a changeable vehicle number and transmitting these numbers through radio waves in response to a call inputted from a road antenna. CONSTITUTION:In order to add at least a part of number plate information to be inherent information in each vehicle to ID plate information in addition to only an ID number to be a simple numeral string, a number plate information storing part 28 such as a exclusive ROM for storing vehicle number plate information is included in the ID plate to independently store the number plate information. Signals from the storing part 28 and an ID number storing part 27 are synthesized in a prescribed format by an ID information synthesizing part 29 and a signal from the synthesizing part 29 is transmitted from a plate antenna part 32 as a radio wave in response to a call from a road antenna part 12. Consequently, whether a vehicle can be entered into a specific area or not can be identified and the generation of illegal entrance can be prevented.