APPARATUS AND METHOD FOR EFFICIENTLY MANAGING POWER-UP TIMER FOR HIGH-SPEED INTER-RAT HANDOVER IN MOBILE COMMUNICATION DEVICE

摘要

A method and an apparatus for efficiently operating a timer for high-speed inter-RAT(Radio Access Technology) handover in a mobile station are provided to minimize the interruption time of a mobile communication service in use and improve the quality of a wireless call service by operating a timer for registration according to inter-RAT idle roaming and maintaining the continuity of the mobile communication service, in case a mobile station moves to a CDMA system from different mobile system. In case a mobile station, performing a WCDMA service in a WCDMA network, moves to a CDMA network, the mobile station decides idle roaming to the CDMA network for handover to a CDMA service(S210-S230). If inter-RAT idle roaming starts, the mobile station activates an idle roaming registration timer. The idle roaming registration timer starts counting till a preset period(S240). Then, the mobile station receives minimum CDMA overhead messages from the CDMA system(S250), and judges whether inter-RAT idle roaming registration is possible(S260). If so, the mobile station executes inter-RAT idle roaming registration(S270), and executes the CDMA service according to inter-RAT idle roaming registration(S280).