Abstract: A channel between a radio terminal (141) of the transmitting side and a radio terminal of the receiving side is geometrically modeled, then the thus obtained channel model is used to recognize the position of a transmitting antenna (151) of a distant station, and a path is estimated from the result of recognition to select a channel in better condition for high-quality communication. Geometrical information on the surrounding conditions is taken in by a geometrical information input device (11) such as a vehicle-mounted camera (120), and a geometrical information recognition device (12) searches the geometrical information for the transmitting antenna (151) of the distant station and outputs position information of the transmitting antenna. And a model generating device (13) generates the channel model based on the geometrical information provided from the geometrical information input device and the antenna position information from the geometrical information recognition device (12).