Method and apparatus of controlling cell deactivation in a wireless communication system
The present invention is directed to a wireless communication system. Specifically, the present invention is directed to a method of receiving information at a user equipment configured with a serving cell in a mobile communication system, and the method comprises activating the serving cell; receiving a first signal from a base station, the first signal including timing advance group assignment information for the serving cell; and deactivating the serving cell if the timing advance group assignment information indicates a second timing advance group different from a first timing advance group assigned to the serving cell.
1. A method of deactivating a serving cell at a user equipment in a mobile communication system, the method comprising:
receiving, by the user equipment, a message from a base station, the message allocating the serving cell to a first timing advance group (TAG);
receiving, by the user equipment, an activation command for the serving cell from the base station;
activating, by the user equipment, the serving cell in accordance with the activation command;
receiving, by the user equipment, a first signal from the base station, the first signal indicating a TAG re-assignment of the serving cell, wherein the first signal includes an identifier of the serving cell and an identifier of a second TAG;
determining, by the user equipment, whether the second TAG is identical to a special TAG pre-defined for a purpose of TAG re-assignment or not; and
deactivating, by the user equipment, the serving cell, only if the second TAG is identical to the pre-defined TAG.
2. The method of claim 1 , wherein the first signal is received via radio resource control (RRC) signaling or medium access control (MAC) signaling.
3. The method of claim 1 , wherein the serving cell is a secondary cell.
4. A user equipment (UE) deactivating a serving cell in a mobile communication system, the UE comprising:
a radio frequency (RF) unit; and
a processor, the processor configured to receive a message from a base station, the message allocating the serving cell to a first timing advance group (TAG);
receive an activation command for the serving cell from the base station;
activate the serving cell in accordance with the activation command, receive a first signal from the base station, the first signal indicating a TAG re-assignment of the serving cell, wherein the first signal includes an identifier of the serving cell and an identifier of a second TAG,
determine whether the second TAG is identical to a special TAG pre-defined for a purpose of TAG re-assignment or not, and
deactivate the serving cell, only if the second TAG is identical to the pre-defined TAG.
5. The UE of claim 4 , wherein the first signal is received via radio resource control (RRC) signaling or medium access control (MAC) signaling.
6. The UE of claim 4 , wherein the serving cell is a secondary cell.