Method and apparatus of sleep mode operation in a multi-carrier system

A mobile station apparatus operating in a wireless communication system, the apparatus comprising:

• a receiver configured to receive configuration information for power management from a base station, wherein the configuration information informs the mobile station a first time period during which the mobile station monitors signals from the base station and a second time period during which the mobile station does not monitor signals from the base station;
• and
• a controller connected to the receiver and configured to communicate with the base station via one or more primary carriers and one or more activated secondary carriers, and to apply the configuration information for power management to the one or more primary carriers and the one or more activated secondary carriers,
• wherein the controller controls the receiver to receive downlink data from the base station via the one or more primary carrier and the one or more activated secondary carriers during the first time period;
• and
• wherein the controller stops the first time period, when a specific Medium Access Control (MAC) message is received by the receiver from the base station.