Patent ID: 8867666

Claim:
A method of controlling signals in a multiple carrier system, the method performed by a user equipment (UE) and comprising: receiving, from a base station, assignment information indicating a plurality of component carriers, which are available to the UE, wherein the assignment information is received in a Radio Resource Control (RRC) message; receiving, from the base station, a Medium Access Control (MAC) message indicating at least one component carrier selected among the plurality of component carriers and valid time information assigned for the at least one component carrier, wherein the MAC message has a logical channel identifier set to a 5-bit value of ‘11011’; in response to the MAC message, transmitting a reception acknowledgement to the base station, wherein the reception acknowledgement is not transmitted if the UE does not successfully receive the MAC message; and if the MAC message instructs the at least one component carrier to be activated, after waiting for a predetermined time, activating the at least one component carrier during an active time period determined based on the valid time information, and deactivating the at least one component carrier after the active time period, wherein the UE performs a blind decoding on a physical downlink control channel (PDCCH) and reports channel quality information (CQI) on a plurality of downlink sub-bands on a whole downlink band for the activated at least one component carrier, wherein the UE does not perform a blind decoding on the PDCCH and reports CQI only on the whole downlink band for the deactivated at least one component carrier, and wherein the predetermined time includes K orthogonal frequency division multiplexing (OFDM) subframes, wherein K is greater than or equal to 1.