Method and apparatus for controlling communication of a portable terminal in a wireless communication system

1. A method of a terminal supporting multi-radio access technologies (multi-RAT) in a wireless communication system, the method comprising:

receiving, from a base station through a first RAT, a control signal to stop receiving packet data convergence protocol (PDCP) data to be received from an access node through a second RAT by deactivation of the second RAT, if the PDCP data to be received from the access node is not detected by the base station during a preset time period from a time point when the PDCP data to be received from the access node is transmitted from the base station to the access node for transmission to the terminal;

transmitting, to the base station through the first RAT in response to the control signal to stop receiving the PDCP data to be received from the access node, a first sequence number of PDCP data which the terminal has last received from the access node; and

receiving, from the base station through the first RAT, PDCP data with a second sequence number that is higher than the first sequence number.

2. The method of claim 1 , further comprising:

starting monitoring of PDCP data to be received from the access node when the second RAT is activated.

3. The method of claim 2 , further comprising,

receiving, if the monitoring of the PDCP data to be received from the access node is started, a beacon signal containing information required to receive the PDCP data to be received from the access node,

wherein the beacon signal contains a first-type beacon signal transmitted with a fixed period or a second-type beacon signal transmitted at a time point between the fixed periods of the first-type beacon signal, and

wherein the second-type beacon signal contains a part of information contained in the first-type beacon signal.

4. The method of claim 2 , further comprising:

receiving, if the monitoring of the PDCP data to be received from the access node is started, a beacon signal containing the information required to receive the PDCP data to be received from the access node;

transmitting, if the beacon signal is not received, a signal containing information for indicating that a change of a base station is required for the second RAT to the base station through the first RAT;

determining a target access node for the second RAT, based on a signal received through the second RAT;

transmitting, to the base station, information regarding the target access node through the first RAT; and

receiving the beacon signal containing the information required to receive PDCP data to be received from the target access node through the second RAT.

5. The method of claim 2 , further comprising:

transmitting a signal for indicating stopping monitoring the PDCP data to be received from the access node; and

stopping the monitoring of the PDCP data to be received from the access node after transmitting the signal.

6. The method of claim 2 , further comprising:

stopping the monitoring of the PDCP data to be received from the access node; and

transmitting, after the monitoring of the PDCP data to be received from the access node is stopped, a signal for indicating the stopping of the monitoring of the PDCP data to be received from the access node.

7. The method of claim 2 , further comprising:

receiving a message including a timer value;

starting a timer with the timer value; and

if the timer expires, stopping the monitoring of the PDCP data to be received from the access node.

8. The method of claim 1 , further comprising:

identifying the first sequence number of the PDCP data which the terminal has last received from the access node.

9. The method of claim 1 , further comprising:

acquiring a second sequence number for indicating the PDCP data to be last received from the access node from the control signal; and

determining whether reception of the PDCP data to be received from the access node is complete based on the second sequence number.

10. An apparatus of a terminal supporting multi-radio access technologies (multi-RAT) in a wireless communication system, the apparatus comprising:

a first transceiver configured to support a first RAT;

a second transceiver configured to support a second RAT; and

at least one processor configured to:

receive, from a base station through the first RAT, a control signal to stop receiving packet data convergence protocol (PDCP) data to be received from an access node through the second RAT by deactivation of the second RAT, if the PDCP data to be received from the access node is not detected by the base station during a preset time period from a time point when the PDCP data to be received from the access node is transmitted from the base station to the access node for transmission to the terminal,

transmit, to the base station through the first RAT in response to the control signal to stop receiving the PDCP data to be received from the access node, a first sequence number of PDCP data which the terminal has last received from the access node, and

receive, from the base station through the first RAT, PDCP data with a second sequence number that is higher than the first sequence number.

11. The apparatus of claim 10 , wherein the at least one processor is further configured to:

start monitoring of the PDCP data to be received from the access node when the second RAT is activated.

12. The apparatus of claim 11 ,

wherein, if the monitoring of the PDCP data to be received from the access node is started, the at least one processor is further configured to receive a beacon signal containing information required to receive the PDCP data to be received from the access node,

wherein the beacon signal contains a first-type beacon signal transmitted with a fixed period or a second-type beacon signal transmitted at a time point between the fixed periods of the first-type beacon signal, and

wherein the second-type beacon signal contains a part of information contained in the first-type beacon signal.

13. The apparatus of claim 11 , wherein the at least one processor is further configured to:

receive a beacon signal containing the information required to receive the PDCP data to be received from the access node, if the monitoring of the PDCP data to be received from the access node is started,

transmit, if the beacon signal is not received, a signal containing information for indicating that a change of a base station is required for the second RAT to the base station through the first RAT,

determine a target access node for the second RAT based on a signal received through the second RAT, if the beacon signal is not received,

transmit, to the base station, information regarding the target access node through the first RAT, and

receive the beacon signal containing the information required to receive PDCP data to be received from the target access node through the second RAT.

14. The apparatus of claim 11 , wherein the at least one processor is further configured to:

transmit a signal for indicating stopping of the monitoring of the PDCP data to be received from the access node; and

stop the monitoring of the PDCP data to be received from the access node after transmitting the signal.

15. The apparatus of claim 11 , wherein the at least one processor is further configured to:

stop the monitoring of the PDCP data to be received from the access node; and

transmit, after the monitoring the PDCP data to be received from the access node is stopped, a signal for indicating the stopping of the monitoring of the PDCP data to be received from the access node.

16. The apparatus of claim 11 ,

wherein the at least one processor is further configured to:

receive a message including a timer value,

start a timer with the timer value, and

if the timer expires, stop monitoring the PDCP data to be received from the access node.

17. The apparatus of claim 10 , wherein the at least one processor is further configured to:

identify the first sequence number of the PDCP data which the terminal has last received from the access node.

18. The apparatus of claim 10 , wherein the at least one processor is further configured to:

acquire a third sequence number for indicating the PDCP data to be last received from the access node from the control signal, and

determine whether reception of the PDCP data to be received from the access node is complete based on the third sequence number.

19. An apparatus of a base station supporting a first radio access technology (RAT), the apparatus comprising:

a transceiver; and

at least one processor configured to:

transmit, to a terminal through the first RAT, a control signal to stop receiving packet data convergence protocol (PDCP) data to be received from an access node through a second RAT by deactivation of the second RAT, if the PDCP data to be to be received from the access node is not detected for a preset time period from a time point when the PDCP data to be received from the access node is transmitted to the access node for transmission to the terminal,

receive, from the terminal through the first RAT in response to the control signal to stop receiving the PDCP data to be received from the access node, a first sequence number of the PDCP data which the terminal has last received from an access node, and

transmit, to the terminal through the first RAT, PDCP data with a second sequence number that is higher than the first sequence number.

20. The apparatus of claim 19 , wherein the control signal comprises a third sequence number for indicating PDCP data to be last received from the access node.