| 摘要 |
PROBLEM TO BE SOLVED: To provide an electronic key system which allows locking or unlocking operation to be performed only from a specific area, even in use of a wave in a long wavelength band.SOLUTION: An on-vehicle transceiver 1 includes a request signal transmitting part 20 which has a plurality of antennas 22a and 22b arranged at positions different from each other on a vehicle, and an answer signal receiving part 30 which receives answer signals. A portable transceiver 2 includes a request signal receiving part 60 which receives each of the request signals, an intensity measuring part 63 which measures the intensity of each of the request signals, an intensity comparison part 64 which compares the intensity of the respective request signals, and an answer signal transmitting part 70 which transmits answer signals. The portable transceiver 2 transmits answer signals when each of the received request signals has an intensity of a predetermined value or higher and the intensity ratio between each of the request signals are in a predetermined range. The on-vehicle transceiver 1 outputs at least one of the control signals for locking and unlocking on the basis of the answer signals. |
