Radio communication system, radio communication apparatus, and retransmission control method

Abstract

In a multiuser MIMO system, entire system throughput achieved during retransmission is significantly enhanced. When an interference signal addressed to another user equipment (UE2) 200b has been demodulated successfully, a user equipment (UE1) 200a holds the demodulated data pertaining to the interference signal, and feeds back ACK information about the UE2 and CQI information achieved after elimination of the interference signal to a radio base station (BS) 100. When the UE2 performs retransmission after ended in a receiving failure and when the UE1 has demodulated the interference signal addressed to the UE2 successfully, the BS changes the distribution of communication resources in such a way that communication resources for the UE2 become larger than those for the UE1. At the time of retransmission, the UE1 eliminates the interference signal from a newly-received signal by use of previously-held demodulated data pertaining to the interference signal, and the UE2 combines data pertaining to the desired signal held during previous receiving failure with data pertaining to the retransmitted signal by means of soft combining.

Dependencies are inferred from the claim text.