METHOD FOR PROCESSING CALL BETWEEN REGIONS OF MOBILE COMMUNICATION SYSTEM

PURPOSE: A method for processing a call between regions of a mobile communication system is provided to form a handoff region that two CSM(Cell Site Modem) ASIC perform a phase tracking between a basic region and an expansion region when a communication region is divided based on the CSM ASIC in a base station of a mobile communication system and normally perform a call process between communication possible regions using an add point, a drop point, a swap point and a RTD(Round Trip Delay). CONSTITUTION: In a state that a mobile terminal normally maintains a call in a basic region(S1), a RTD value is detected(S2). In the case that the detected RTD value is an extent-call-add point(S3), the call is set in a CSM ASIC of an expansion region and the upper most terminal for a signal transmission and receipt is disabled(S4). In the case that the detected RTD value is a basic-call/expansion-call-switch point(S5), a transmission/receipt of the CSM ASIC of the expansion region is enabled and the transmission/receipt of the CSM ASIC of the basic region is disabled(S6). In the case that the detected RTD value is a basic-call-drop point(S7), a call release is performed in the CSM ASIC of the basic region and the call of the mobile terminal is normally maintained in the expansion region(S8).