A base station apparatus (radio transmission apparatus) transmits a radio signal of data to a mobile terminal apparatus (communication apparatus of a transmission destination). The mobile terminal apparatus receiving the radio signal determines (ST1010) information (CQI) on a downlink transmission rate enabling reception in the mobile terminal apparatus based on reception quality such as CIR to transmit to the base station apparatus. The base station apparatus extracts a CQI value from the received radio signal, while obtaining likelihood of received data (ST1020), and corrects the CQI value based on the likelihood (ST1030). Then, based on the corrected CQI value, the base station apparatus determines a downlink transmission rate (ST1040). By this means, even when the radio transmission apparatus erroneously receives the transmission rate request transmitted from the communication apparatus of the transmission destination, the communication apparatus is prevented from erroneously receiving the data transmitted from the radio transmission apparatus.