In a wireless communication system in which a plurality of base stations each forming a directional beam in one direction are disposed along a predetermined path, each base station estimates a distance from installed in a mobile body moving along the path if the TE enters a cell area of the corresponding base station; and controls the transmission power using a distance from the estimated TE so that a difference between received signal strength of the corresponding base station and the received signal strength of neighboring base stations measured by the TE in a cell boundary area between the base stations does not exceed a predetermined threshold value.