METHOD AND AN APPARATUS FOR SEARCHING A CELL OF A MOBILE TERMINAL FOR HANDOVER BETWEEN AN ASYNCHRONOUS SYSTEM AND A SYNCHRONOUS SYSTEM, PARTICULARLY FOR REDUCING A PINGPONG PHENOMENON BY PERFORMING HANDOVER TO A CDMA2000 NETWORK IF EACH SIGNAL QUALITY OF NEIGHBOR CELLS EXCEEDS A PRE-SET THRESHOLD VALUE

摘要

PURPOSE: A method and apparatus for searching a cell of a mobile terminal for handover between an asynchronous system and a synchronous system are provided to maintain stability of a system by performing handover to a CDMA2000 network after a mobile terminal is completely out of an area of a WCDMA network. CONSTITUTION: A dual-mode mobile terminal is in an idle mode and enters a boundary cell area of a WCDMA network(610). The mobile terminal receives the first scrambling code and an SIB(System Information Block) from a base station of the WCDMA network(620). The mobile terminal checks signal strengths received from a boundary cell in which the mobile terminal is located and other adjacent cells(630). The mobile terminal checks whether signal qualities of the adjacent cells exceed a pre-set threshold value(640), and if so, the mobile terminal checks stability of a channel state according to communication of the adjacent cells and performs handover to a CDMA2000 network(650). The mobile terminal performs communication according to a CDMA system(660).