Techniques for component carrier-specific reconfiguration are disclosed. A wireless transmit/receive unit (WTRU) is capable of transmitting or receiving via multiple component carriers. The WTRU may perform component carrier reconfiguration on a component carrier basis to add, remove or replace a component carrier. Discontinuous reception (DRX) and/or discontinuous transmission (DTX) may be performed on at least one component carrier, wherein DRX and/or DTX patterns on the component carriers may not overlap each other. A random access procedure may be performed at the target cell on one component carrier while other component carriers are inactive. The component carrier-specific reconfiguration or handover of a component carrier or a channel may be implemented in coordinated multiple point transmission (CoMP), wherein a handover of a control channel, not a traffic channel, may be performed. Alternatively, a handover of a traffic channel may be performed.