Patent ID: 8755298

Claim:
A method of supporting random access of a user equipment (UE) in a base station of a wireless communication system supporting carrier aggregation, the method comprising: transmitting, to the UE, an activation message for activating a plurality of uplink component carriers (UL CCs) to be used for the carrier aggregation after a first random access is finished, wherein the activation message includes information on a dedicated physical random access channel (PRACH) preamble for controlling timing advance of the plurality of UL CCs in each of UL CC groups which divide the plurality of UL CCs into UL CC groups such that UL CCs using the same timing advance belong to the same group; and receiving one or more dedicated PRACH preambles for a second random access to perform controlling of timing advance of the plurality of UL CCs from the UE, wherein the activation message includes one or more dedicated PRACH preambles to be used for each UL CC group during a procedure of the second random access, and wherein one or more of the dedicated PRACH preambles for the second random access are received from the UE through a reference carrier of each of the UL CC groups.