A method for transmitting, by a base station, signals in a communication system. The base station transmits, to a mobile station via a primary carrier band of the mobile station, carrier aggregation configuration information informing the mobile station of a subsidiary carrier band for the mobile station. The base station receives, from the mobile station, control information for the subsidiary carrier band via the primary carrier band. The carrier aggregation configuration information includes a physical identification of a frequency allocation band used as the subsidiary carrier band and a logical identification assigned to the subsidiary carrier band for the mobile station. The physical identification includes one of plural absolute frequency band indexes assigned to frequency allocation bands available in the communication system. The logical identification includes a logical index assigned to the subsidiary carrier band identifying the subsidiary carrier band from among a plurality of frequency allocation bands.