METHOD AND APPARATUS FOR TRANSMITTING CIRCUIT SWITCHED CALL TO AN IDLE USER EQUIPMENT IN A COMMON ROUTING AREA OF A MOBILE COMMUNICATION SYSTEM

摘要

A method for transferring a circuit switched call to an idle user terminal located in a common routing area of a mobile communication system and an apparatus thereof are provided to enable all the CS(Circuit Switched) voice calls to be converted into PS(Packet Switched) data calls by notifying an HSS(Home Subscriber Server) that the terminal is located in the common routing area, and to reduce overhead in processes for converting CS voice calls into PS data calls, which collaterally occur in accordance with frequent movements of the terminal in the common routing area. A method for transferring a circuit switched call to an idle user terminal located in a common routing area of a mobile communication system comprises the following several steps. The terminal transmits a TAU(Tracking Area Update) request message to an AGW(Access Gateway) which is an entity of an LTE(Long Term Evolution) core network(201). The AGW compares a tracking area, where the AGW is currently located, with routing area information in a 3G network transmitted by the terminal(203). If the tracking area information is the same as the routing area information, the terminal transmits common routing area indication information to an HSS in order to notify the HSS that the tracking area information is the same as the routing area information(205). The HSS stores user ID information together with the common routing area indication information(207). The HSS transmits a response message regarding the common routing area indication information to the AGW(209).