A base station carries out training for obtaining correlation information that correlates the reception quality of a packet channel transmitted from a terminal and the transmission power of an associated channel, and based on the correlation information, uses the transmission power of the associated channel to obtain a predicted value of the reception quality of the packet channel, and controls the transmission of data through the packet channel based on that predicted value. The base station transmits through the associated channel transmission control information for controlling the transmission of the reception quality of the packet channel by the terminal. The terminal controls the transmission of the reception quality of the packet channel based on the transmission control information included in the data of the associated channel transmitted from the base station.