HAND FREE ACCESS DEVICE AND ENGINE START DEVICE FOR AUTOMOBILE

摘要

PROBLEM TO BE SOLVED: To provide a hand free access device capable of sufficiently covering a passenger room and the external area of the automobile using the minimum antenna. SOLUTION: This is a car authorizing device permitting the engine start or hand free access for the car; this authorizing device is connected to a single internal antenna 2 inside the passenger room in the car; at least two different transmitting powers can be used for transmitting data; the first transmitting power is capable of covering the first region including part of the passenger room, the second transmitting power is higher than the first transmitting power, and the internal antenna is able to cover both the whole of the passenger room and the external region of the car.