摘要 |
In a mobile communication system in which a plurality of component carriers are used, transmitting and receiving control information of HARQ effectively is realized. In a mobile communication system in which a base station apparatus (100) sets a plurality of downlink component carriers for a mobile station apparatus (200), the base station apparatus (100) transmits a downlink transport block to the mobile station apparatus (200) on one or a plurality of downlink component carriers among the plurality of downlink component carriers, and the mobile station apparatus transmits, to the base station apparatus (100), control information of HARQ for the downlink transport block on any one of physical uplink control channel resources corresponding to the one or plurality of downlink component carriers on which the downlink transport block has been transmitted. |