The influence of multipath on the positioning calculation based on positioning signals transmitted from satellites is reduced. A self-position is estimated using a positioning calculation result based on a positioning signal transmitted from a satellite. Movement of a mobile body is controlled on the basis of the estimated self-position. A multipath reduction action signal is output when the mobile body is in a multipath environment. The mobile body is controlled so as to take a multipath reduction action when the mobile body is in a predetermined movement state and the multipath reduction action signal is output.