Apparatus and method for performing handover in multiple component carrier system

1. A method of a target Base Station (BS) performing handover in a multiple component carrier system, the method comprising:

receiving service state information, including information about at least one candidate cell, from a source BS through a handover request message;

calculating a final determination value for determining a final cell for a User Equipment (UE) which is a subject of the handover based on the service state information;

selecting the final cell by comparing the final determination value and the information about the candidate cell; and

sending a handover request Acknowledgment (ACK) message, including information about the selected final cell, to the source BS,

wherein the service state information comprises at least one of a Guaranteed Bit Rate (GBR) which is a minimum bit rate for guaranteeing Quality of Service (QoS) of the UE, an Aggregated Maximum Bit Rate (AMBR) which is a maximum bit rate for guaranteeing the QoS of the UE in relation to bearers other than a bearer to which the GBR is applied, and an Average Throughput (AT) of packets for guaranteeing the QoS of the UE.

2. The method of claim 1 , wherein:

the service state information comprises a measurement report configured by the UE which is the subject of the handover, and

the information about the at least one candidate cell is included in the service state information in a form of the measurement report.

3. The method of claim 1 , wherein calculating the final determination value comprises determining values, determined based on the GBR and the AMBR, as the final determination value.

4. The method of claim 3 , wherein selecting the final cell comprises selecting the candidate cell, having a bit rate existing within the GBR and a range of a sum of the GBR and the AMBR, as the final cell.

5. The method of claim 4 , wherein selecting the final cell comprises selecting a plurality of the candidate cells as the final cells, when a sum of throughputs of the plurality of candidate cells falls within a range between the final determination values determined based on the GBR and the AMBR.

6. The method of claim 1 , wherein calculating the final determination value comprises determining the Average Throughput (AT), included in the service state information, as the final determination value.

7. The method of claim 6 , wherein the candidate cell having a throughput existing within a range determined by the AT is selected as the final cell.

8. The method of claim 7 , wherein when a sum of throughputs of the plurality of candidate cells exists within the range determined by the AT, the plurality of candidate cells are selected as the final cells.

9. The method of claim 1 , further comprising sending, to the source BS, the handover request ACK message comprising a final cell list, including at least one combination of a logical index of the selected final cell, a physical index of the selected final cell, and a frequency of the selected final cell.

10. A target Base Station (BS) performing handover in a multiple component carrier system, the target BS comprising:

a transceiver for sending and receiving information about the handover to and from a source BS; and

a processor configured to perform processes comprising:

a list configuration process to select a serving cell to be applied to a User Equipment (UE) which will handover and configuring a list regarding the selected serving cell; and

a cell configuration process to configure the selected serving cell,

wherein the transceiver receives service state information about a state of service, provided to the UE, from the source BS of the UE, and

the list configuration process selects the serving cell for the UE based on the received service state information,

wherein:

the list configuration process selects the serving cell for the UE from one or more handover candidate cells based on information about the candidate cell or information about the service provided to the UE or both,

the service state information comprises the information about the one or more handover candidate cells, the information about the candidate cell and/or the information about the service provided to the UE,

the information about the service provided to the UE comprises at least one of a Guaranteed Bit Rate (GBR) which is a minimum bit rate for guaranteeing the service provided to the UE, an Aggregated Maximum Bit Rate (AMBR) which is a maximum bit rate for guaranteeing QoS of the UE in relation to bearers other than a bearer to which the GBR is applied, and information about candidate cells with an Average Throughput (AT) of packets for guaranteeing the QoS of the UE, and

the information about the candidate cell comprises a measurement value measured by the UE.

11. The target BS of claim 10 , wherein the list configuration process selects the candidate cell, having a bit rate corresponding to a range between the GBR and a sum of the GBR and the AMBR, as the serving cell.

12. The target BS of claim 10 , wherein the list configuration process selects the candidate cell, having a throughput higher than the AT, as the serving cell.

13. A method of a source Base Station (BS) performing handover in a multiple component carrier system, the method comprising:

receiving a measurement report from a User Equipment (UE);

configuring a candidate cell list for handover of the UE based on the measurement report;

sending a handover request message for the UE to a target BS;

receiving a handover request ACK message for the UE from a target BS;

determining the handover of the UE; and

sending a handover command message to the UE,

wherein the candidate cell list comprises information about at least one candidate cell, and

the candidate cell list is included in the handover request message along with information about service provided to the UE and transmitted to the target BS,

wherein the information about the service provided to the UE comprises at least one of a Guaranteed Bit Rate (GBR) which is a minimum bit rate for guaranteeing the service provided to the UE, an Aggregated Maximum Bit Rate (AMBR) which is a maximum bit rate for guaranteeing Quality of Service (QoS) of the UE in relation to bearers other than a bearer to which the GBR is applied, and information about candidate cells with an Average Throughput (AT) of packets for guaranteeing the QoS of the UE.

14. A source Base Station (BS) performing handover in a multiple component carrier system, comprising:

a transceiver for receiving a measurement report from a User Equipment (UE) and sending and receiving handover information about the UE; and

a processor configured to perform a list configuration process to select a handover candidate cell for the UE based on the measurement report of the UE and configure a list including the selected handover candidate cell,

wherein the transceiver sends the list of the handover candidate cell, together with service information about the UE, to a target BS related to handover of the UE,

wherein the service information about the UE comprises at least one of a Guaranteed Bit Rate (GBR) which is a minimum bit rate for guaranteeing the service provided to the UE, an Aggregated Maximum Bit Rate (AMBR) which is a maximum bit rate for guaranteeing Quality of Service (QoS) of the UE in relation to bearers other than a bearer to which the GBR is applied, and information about candidate cells with an Average Throughput (AT) of packets for guaranteeing the QoS of the UE.