A mobile station (MS) receives one or more first physical downlink shared channels (PDSCH) on one or more first downlink component carriers and a plurality of second PDSCHs on a plurality of second downlink component carriers. The MS transmits, in a subframe, a first physical uplink channel with first ACK/NACK in a first uplink component carrier, the first ACK/NACK being provided for the one or more first PDSCHs received on the one or more first downlink component carriers, and a second physical uplink channel with second ACK/NACK in a second uplink component carrier, the second ACK/NACK being provided for the plurality of second PDSCHs received on the plurality of second downlink component carriers.