Abstract: A method and apparatus of cell searching in a wireless communication is disclosed. A method of cell searching in a user equipment of a wireless communication system, which supports a multi-mode, comprises the steps of generating a list of neighbor cells by measuring a power of each of the neighbor cells of first radio access technology (RAT) when the user equipment is operating in second RAT; and a first search step of searching for a cell, which can serve the user equipment, from the cells included in the list of neighbor cells if radio link failure is occurred in the second RAT.

Abstract: A method for performing handover in a dual-mode terminal is disclosed. The method for performing handover in a dual-mode terminal includes receiving an Internet Protocol (IP) packet from a personal computer (PC), and transmitting the received IP packet to a serving network; upon receiving a handover message from the serving network, stopping reception of the IP packet from the PC; forwarding residual packets from a first processor corresponding to the serving network to a second processor corresponding to a target network; upon handover completion and completion of the forwarding of the residual packets, restarting reception of the IP packet from the PC; and transmitting the residual packets to the target network.

Abstract: A method and apparatus for processing inter-RAT measurement in a dual modem device are disclosed. A method for processing inter-RAT measurement in a dual modem device includes receiving, by a first processor communicating with a first communication network, a measurement control signal including a parameter for signal measurement from the first communication network; transmitting, by the first processor, timing information based on a system frame number (SFN) and a global time to a second processor; acquiring time synchronization for the inter-RAT measurement between the first processor and the second processor on the basis of the system frame number (SFN) and the global time; transmitting the parameter from the first processor to the second processor; and measuring, by the second processor, a signal of a second communication network using the parameter.

Abstract: A method and apparatus for performing a NAS procedure in a NAS module of a multi-mode terminal are disclosed. A method for performing a NAS procedure in a multi mode NAS (mNAS) module of a multi-mode terminal includes receiving a NAS procedure request signal from a user, and selecting a first NAS; transmitting the NAS procedure request signal to a NAS module corresponding to the first NAS; receiving a NAS procedure response signal, that includes an execution result of a NAS procedure between the NAS module corresponding to the first NAS and a network, from the NAS module corresponding to the first NAS; performing synchronization between the NAS module corresponding to the first NAS and a NAS module corresponding to a second NAS according to the NAS procedure execution result; and transmitting a NAS procedure response signal including the NAS procedure execution result to the user.

Abstract: A method and apparatus of cell searching in a wireless communication is disclosed. A method of cell searching in a user equipment of a wireless communication system, which supports a multi-mode, comprises the steps of generating a list of neighbor cells by measuring a power of each of the neighbor cells of first radio access technology (RAT) when the user equipment is operating in second RAT; and a first search step of searching for a cell, which can serve the user equipment, from the cells included in the list of neighbor cells if radio link failure is occurred in the second RAT.

Abstract: A method and apparatus for processing inter-RAT measurement in a dual modem device are disclosed. A method for processing inter-RAT measurement in a dual modem device includes receiving, by a first processor communicating with a first communication network, a measurement control signal including a parameter for signal measurement from the first communication network; transmitting, by the first processor, timing information based on a system frame number (SFN) and a global time to a second processor; acquiring time synchronization for the inter-RAT measurement between the first processor and the second processor on the basis of the system frame number (SFN) and the global time; transmitting the parameter from the first processor to the second processor; and measuring, by the second processor, a signal of a second communication network using the parameter.

Abstract: A method and apparatus for performing a NAS procedure in a NAS module of a multi-mode terminal are disclosed. A method for performing a NAS procedure in a multi mode NAS (mNAS) module of a multi-mode terminal includes receiving a NAS procedure request signal from a user, and selecting a first NAS; transmitting the NAS procedure request signal to a NAS module corresponding to the first NAS; receiving a NAS procedure response signal, that includes an execution result of a NAS procedure between the NAS module corresponding to the first NAS and a network, from the NAS module corresponding to the first NAS; performing synchronization between the NAS module corresponding to the first NAS and a NAS module corresponding to a second NAS according to the NAS procedure execution result; and transmitting a NAS procedure response signal including the NAS procedure execution result to the user.

Abstract: A method for performing handover in a dual-mode terminal is disclosed. The method for performing handover in a dual-mode terminal includes receiving an Internet Protocol (IP) packet from a personal computer (PC), and transmitting the received IP packet to a serving network; upon receiving a handover message from the serving network, stopping reception of the IP packet from the PC; forwarding residual packets from a first processor corresponding to the serving network to a second processor corresponding to a target network; upon handover completion and completion of the forwarding of the residual packets, restarting reception of the IP packet from the PC; and transmitting the residual packets to the target network.