DUAL MODE MOBILE COMMUNICATION TERMINAL AND METHOD FOR CONTROLLING HANDOVER IN THE DUAL MODE MOBILE COMMUNICATION TERMINAL

摘要

A dual-mode mobile communication terminal and a handover control method in the dual-mode mobile communication terminal are provided to obtain and store synchronous information of a synchronous network in idle time, and to detect synchronous information of the synchronous network to compare the detected information with the synchronous information obtained for an idle time, when the terminal enters the synchronous network, in order to use the comparison result for transition to the synchronous network. A terminal detects synchronous information of a synchronous system by using instant time in asynchronous idle mode(S50-S58), and calculates a synchronous frame time difference between synchronous and asynchronous systems by using the detected synchronous information(S60). The terminal stores the synchronous information and the frame time difference in a memory(S62). If a call setup request is generated in the asynchronous idle mode, the terminal establishes a call with the asynchronous system, and performs call processing with the asynchronous system(S64-S80). If a handover event to the synchronous system occurs, the terminal sets a CM(Compressed Mode), and receives synchronous information from the synchronous system(S82-S86). The terminal compares the received synchronous information with the synchronous information stored in the memory(S88). If a handover message indicative of transition to the synchronous system from the asynchronous system is received, the terminal establishes a call with the synchronous system, and performs a call cancellation procedure with the asynchronous system while performing call processing with the synchronous system(S90-S98).