Apparatus and method for uplink synchronizing in multiple component carrier system

A communication apparatus comprising:

• a processor;
• and
• a memory operably coupled to the memory,
• wherein the processor, when executing program instructions stored in the memory, is configured to:
• cause the communication apparatus to receive a message for RRC Connection Reconfiguration from an eNodeB (eNB), wherein the message for RRC Connection Reconfiguration comprises a first index for a first secondary cell (scell) and a second index for a second scell;
• cause the communication apparatus to receive a PDCCH order from the eNB, wherein the PDCCH order comprises a random access preamble index;
• cause the communication apparatus to transmit a random access preamble associated with the random access preamble index to the eNB using the first scell corresponding the first index of the message;
• cause the communication apparatus to receive a random access response from the eNB using a primary cell, wherein the random access response includes a timing advance value;
• and
• cause the communication apparatus to transmit user data to the eNB using the second scell corresponding the second index of the message at least based on the timing advance value,
• wherein the PDCCH order is received using the first scell corresponding the first index of the message.

A device for a user equipment (UE), the device comprising:

• a processor;
• and
• a memory operably coupled to the memory,
• wherein the processor, when executing program instructions stored in the memory, is configured to:
• cause the UE to receive a message for RRC Connection Reconfiguration from an eNodeB (eNB), wherein the message for RRC Connection Reconfiguration comprises a first index for a first secondary cell (scell) and a second index for a second scell;
• cause the UE to receive a PDCCH order from the eNB, wherein the PDCCH order comprises a random access preamble index;
• cause the UE to transmit a random access preamble associated with the random access preamble index to the eNB using the first scell corresponding the first index of the message;
• cause the UE to receive a random access response from the eNB using a primary cell,
• wherein the random access response includes a timing advance value;
• and
• cause the UE to transmit user data to the eNB using the second scell corresponding the second index of the message at least based on the timing advance value,
• wherein the PDCCH order is received using the first scell corresponding the first index of the message.