A wireless communication system in which encoded bits are transmitted from a first wireless communication device to a second wireless communication device and redundancy information for decoding the encoded bits is transmitted from the first wireless communication device to the second wireless communication device when the second wireless communication device fails to decode the encoded bits, the wireless communication system comprising: a selector configured to select one or more communication patterns that respectively satisfy a requested quality, each of the communication patterns indicating a combination of a plurality of parameters including a coding rate and a number of iterations of an iterative decoding; a transmission data length calculator configured to calculate, for each of the communication patterns selected by the selector, a transmission data length that indicates a length of the redundancy information wherein the second wireless communication device is expected to successfully decode the encoded bits by using the redundancy information; a transmission latency calculator configured to calculate, for each of the communication patterns selected by the selector, a transmission latency between the first wireless communication device and the second wireless communication device based on the transmission data length calculated by the transmission data length calculator, wherein the transmission latency includes a time needed to propagate a signal from the first wireless communication device to the second wireless communication device, a time of processing performed by a demodulator of the second wireless communication device, and a time of processing performed by a decoder of the second wireless communication device; and a retransmission parameter generator configured to generate a retransmission parameter that indicates a communication pattern with lowest transmission latency among the communication patterns selected by the selector, wherein the first wireless communication device transmits the redundancy information according to the retransmission parameter, and the second wireless communication device decodes the encoded bits by using the redundancy information according to the retransmission parameter. a selector configured to select one or more communication patterns that respectively satisfy a requested quality, each of the communication patterns indicating a combination of a plurality of parameters including a coding rate and a number of iterations of an iterative decoding; a transmission data length calculator configured to calculate, for each of the communication patterns selected by the selector, a transmission data length that indicates a length of the redundancy information wherein the second wireless communication device is expected to successfully decode the encoded bits by using the redundancy information; a transmission latency calculator configured to calculate, for each of the communication patterns selected by the selector, a transmission latency between the first wireless communication device and the second wireless communication device based on the transmission data length calculated by the transmission data length calculator, wherein the transmission latency includes a time needed to propagate a signal from the first wireless communication device to the second wireless communication device, a time of processing performed by a demodulator of the second wireless communication device, and a time of processing performed by a decoder of the second wireless communication device; and a retransmission parameter generator configured to generate a retransmission parameter that indicates a communication pattern with lowest transmission latency among the communication patterns selected by the selector, wherein the first wireless communication device transmits the redundancy information according to the retransmission parameter, and the second wireless communication device decodes the encoded bits by using the redundancy information according to the retransmission parameter.