Patent ID: 7991399

Claim:
A mobile communication device comprising: a cellular communication module adapted to communicate with a wireless cellular network: a Wi-Fi communication module adapted to communicate with an access point associated with a Wi-Fi network using a VoIP protocol; a switching circuit adapted to automatically switch operation between the cellular communication module and the Wi-Fi communication module; a timer; and a Wi-Fi signal monitor; wherein if the Wi-Fi signal monitor detects that a level of a Wi-Fi signal is greater than a first predefined threshold value V th1 , the timer is activated to begin a first time window of a first predefined size T 1 , wherein if during T 1 the Wi-Fi signal monitor detects that the level of the Wi-Fi signal remains equal to or greater than V th1 , at the expiration of the first time window the switching circuit sends a tear-down signal to the cellular communication module and a link-up signal to the Wi-Fi communication module, wherein said tear-down signal causes the cellular communication module to discontinue handling a previously established cellular communication and wherein said link-up signal causes the Wi-Fi communication module to handle the previously established cellular communication via a VoIP network, wherein if the mobile communication device detects both the Wi-Fi signal from the access point and a cellular signal from the wireless cellular network before establishing a communication link, the mobile communication device attempts to establish communication with the access point before attempting to establish communication with the wireless cellular network, wherein said tear-down signal causes the cellular communication module to go into a sleep mode.