A transmitting unit divides a transmit data into a plurality of code blocks, and encodes each of the plurality of code blocks to generate a transmission signal. The transmitting unit transmits the transmission signal, and a receiving unit receives the transmission signal as a reception signal. The receiving unit receives performs an iterative decoding to each of the plurality of code blocks of the reception signal. The iterative decoding is terminated to a first code block group in which an error has not been detected before a first setting iteration count. The receiving unit, when being an error in the reception signal, transmits a retransmission request feedback data which contains a NACK data and a data indicating the first code block group to the transmitting unit,. First resources are assigned for each of the plurality of code blocks of the transmission signal. The transmitting unit assigns resources of the first code block group of the plurality of code blocks of the transmission signal to second resources which are fewer than the first resources, based on the retransmission request feedback data, and retransmits the transmission signal to the receiving unit.