A radio apparatus is disclosed for improving the throughput of data transfer using a HARQ-based automatic retransmission. The radio apparatus performs a HARQ-based automatic retransmission. In this event, a redundancy version control unit identifies a redundancy version in the retransmission based on a redundancy version in the preceding transmission in which the need for retransmission arose. A HARQ processing unit performs rate matching on each of the systematic bits and parity bits of data to be retransmitted in accordance with the redundancy version identified by the redundancy version control unit.