Patent ID: 8520655

Claim:
A wireless communication system comprising: a transmitting device that transmits data in frame units that are modulated based on MCS (Modulation and Coding Scheme) determined by adaptive modulation and an MCS identifier that specifies MCS; and a receiving device, which is configured to conduct wireless communication with the transmitting device, and demodulate received data based on MCS specified by the received MCS identifier; wherein the transmitting device comprises a transmission data maintaining unit that maintains transmission data and an MCS identifier of MCS modulating the transmission data in association with a frame identifier that specifies a frame of the transmission data, a data modulating unit that modulates the transmission data based on the maintained MCS, and a data transmitting unit that transmits the modulated data in sequence; wherein the receiving device comprises, a data receiving unit that receives data from the transmitting device; a data demodulating unit that demodulates the received data, an error detecting unit that detects an error of the demodulated data, a demodulated data maintaining unit which, when an error has been detected in the demodulated data, maintains the demodulated data and an MCS identifier of the data in association with the frame identifier, and an ARQ transmitting unit which, when an error has been detected in the demodulated data, transmits ARQ (Automatic Repeat Request) including a frame identifier of the data and an identifier of an error part; wherein the data modulating unit modulates the error part of the data maintained in the transmission data maintaining unit and specified by the frame identifier and the identifier of the error part in the ARQ based on the MCS maintained in the transmission data maintaining unit, after a predetermined frame from receiving the ARQ; wherein the data transmitting unit retransmits the modulated data; wherein the data demodulating unit demodulates an error part of the received data based on the MCS maintained in the demodulated data maintaining unit; and wherein the receiving device further comprises a chase combining unit for chase combining the demodulated error part and the data maintained in the demodulated data maintaining unit.