PURPOSE: To realize the antenna system in which the reception capability of the antenna mounted on a vehicle is enhanced and a reception area is expanded substantially.
CONSTITUTION: The antenna system in which two antennas 1, 2 having an electric field component in the same direction as a radio wave of an on-road antenna are arranged at an optional distance in a same direction on a plane view in the forward/backward direction is provided with a phase setting means 6 able to set an exciting phase of at least one antenna in the antennas 1, 2 optionally, the directivity of the antenna system is formed in front of the vehicle when a radio wave from the on-road antenna advances to a reception area and the directivity of the antenna system is formed in the backward direction of the vehicle when the radio wave escapes from the reception area thereby expanding the reception area substantially.
TANIGUCHI TATSUAKI
TAKAO KEIJI
OKAMOTO TOSHIHIKO
