Patent ID: 7729723

Claim:
A dual-mode mobile terminal capable of accessing a synchronous mobile communication system and an asynchronous mobile communication system, the terminal comprising: a key input unit including a call switching key and a call end key, said call switching key being used for switching between a call from the synchronous mobile communication system and a call from the asynchronous mobile communication system, and said call end key being used for ending calls from the mobile communication systems; a controller for determining, during communication of one call received from one of the synchronous and asynchronous mobile communication systems, whether another call is received from the other mobile communication system, and notifying a user of the terminal of the receipt of another call if it is determined that another call has been received from the other mobile communication system, and preparing a communication environment for communication of another call if the call switching key is pressed by the user to allow the user to perform the communication of another call while maintaining a communication channel that has been established for the communication of the one call; a first modem for the synchronous mobile communication system; a second modem for the asynchronous mobile communication system; a first switch connected directly to a microphone for switching said microphone between the first and second modems; and a second switch connected directly to a speaker for switching said speaker between said first and second modems, wherein if the call end key is pressed, the controller ends one call received from one of the synchronous and asynchronous mobile communication systems corresponding to the pressed call end key by sending a call end message to the one mobile communication system, and prepares a communication environment for communication of another call that has not been ended.