Patent attributes
A vehicle door control system provides increased usability convenience to users by a function for automatically opening and closing vehicle doors. When a response signal has been continuously received over a predetermined period from a portable device in response to a request signal periodically transmitted from a vehicle unit, it can be inferred that the holder of the portable device has not merely passed by the vehicle but stays in the vicinity of the vehicle with the will to ride in the vehicle. Therefore, vehicle doors having the automatic opening/closing function are unlocked and automatically opened. This eliminates a need for the holder of the portable device to command the operations of unlocking and automatically opening the vehicle doors.
