First and second transmission channel correction circuits generate a corrected data signal and a corrected control signal by executing a transmission channel correction to a data signal transmitted by a first modulation method and a control signal transmitted by a second modulation method that is more tolerant to noise than the first modulation method. The data signal and control signal are included in reception signals received by first and second antennas. First and second quality information calculation circuits calculate quality information indicating quality of the reception signal on the basis of the corrected control signal. A combination ratio calculation circuit calculates a combination ratio of the corrected data signals generated by the first and second transmission channel correction circuits, on the basis of two types of quality information calculated by the first and second quality information calculation circuits. A combination circuit executes combination at the combination ratio.