An aggregation station: receives, from each of the base stations, communication path information with each of accommodated user terminals, for each user terminal; in a case where it is determined that the two of the base stations and the two user terminals are arranged on the straight line, generates first information for performing setting such that a transmission beam of any one of the base stations arranged on the straight line is stopped and another of the base stations non-orthogonally superimposes and multiplexes pieces of transmission data for the two respective user terminals with a predetermined power difference or power ratio; and controls the transmission beam of each of the two of the base stations arranged on the straight line on the basis of the first information.