A
dual mode mobile terminal has a
dual mode in which said mobile terminal can be connected to any of two different
wireless communications systems (hereinafter referred to as systems 1 and 2). The mobile terminal can be connected to optimum
wireless communications system by considering conditions at which the mobile terminal is (
moving speed, communication
data rate) even if it is in the state of communicating using any of systems 1 and 2. The mobile terminal (3) which can be connected to any of the
system 1 having a wide service area and medium and low communication
data rate and the
system 2 having a local service area and high communication
data rate determines whether or not it is in the service area of the systems 1 and 2. Based upon the
moving speed and / or the communication data rate of the current mobile terminal (3), the mobile terminal (3) is connected to the
system 1 or 2 if the
moving speed is higher or lower than a predetermined threshold, respectively, and is connected to the system 2 or 1 if the communication data rate is higher or lower than a predetermined threshold, respectively, irrespective of whether the mobile terminal is in the communicating state or not. Prior to connection, selection of the
wireless system is informed to the user and the connection may be made in accordance with an instruction from the user.