A hardware is used to perform an SSDT processing, thereby avoiding performance degradation than otherwise would occur due to load increase caused by a software processing, and thereby realizing a base station that can instantaneously perform a transmission control and provide a high speed site selection. In order to perform a site selection diversity power control (SSDT) for the purpose of reducing the amount of interference that would be caused by transmitting the same data to a plurality of cells or antennas during soft-handover, an encode processing part (1) is used to add a transmission control bit to the transmitted data. In response to this transmission control bit, a transmission control signal selecting circuit (206) selects a transmission control signal of destination. An output control circuit (207) receives, as its inputs, a transmission spread signal and the transmission control signal to perform an output control and instantaneously perform a transmission control, thereby realizing a high-speed site selection.