System and method for setting communication availability of electronic key

摘要

A system for setting communication availability of an electronic key for transmitters in a communication subject of the electronic key. The electronic key receives a normal signal from one of the transmitters and returns an ID code. A dummy signal transmission unit of the communication subject generates a dummy signal synchronized with the normal signal and transmits the dummy signal from a transmitter that does not transmit the normal signal. A signal output unit of the electronic key receives a combined signal of the normal and dummy signals and outputs a characteristic signal that varies according to the level of the combined signal. A location determination unit of the electronic key determines the transmitter located near the electronic key from a conforming value corresponding to a variation in the characteristic signal.