Patent ID: 8830969

Claim:
A method of reconfiguring Component Carriers (CCs) at a user equipment (UE) in a wireless communication system supporting carrier aggregation, the method comprising: receiving a CC reconfiguration command from a base station (BS) through a downlink (DL) CC of a plurality of first CCs; reconfiguring serving CCs by changing at least one of the first CCs to one or more second CCs according to the CC reconfiguration command; and transmitting a dedicated random access preamble to the BS after the serving CCs are reconfigured, the dedicated random access preamble indicating that reconfiguration of serving CCs has been completed, wherein, when M>K (the M is a number of the first CCs and the K is a number of Reconfigured CCs of the first CCs), the dedicated random access preamble is transmitted through a non-reconfigured uplink (UL) CC, among the plurality of the first CCs, and wherein, when M=K, the dedicated random access preamble is transmitted through a UL CC of the second CCs.