Controlling method and data call handover method for dual band/dual mode mobile communication terminal

摘要

In the data call handover method, the mobile communication terminal registers a Mobile Internet Protocol (MIP address) through an asynchronous mobile communication network and receives data call service when a data call connection event is initiated by the mobile communication terminal. It is determined whether the mobile communication terminal has entered an area in which the asynchronous mobile communication network and a synchronous mobile communication network overlap. If the mobile communication terminal has entered the overlap area, it is determined whether to perform handover to the synchronous mobile communication network based on the intensity of a signal of the asynchronous mobile communication network. If handover is to be performed, a data call between the mobile communication terminal and the synchronous mobile communication network is established and the MIP address is registered. The service of the data call, which is provided by the asynchronous mobile communication network, is linked with the service of the synchronous mobile communication network. The data call between the mobile communication terminal and the asynchronous mobile communication network is released.