Method of seamless roaming between wireless local area networks and cellular carrier networks

A system for managing calls between a wireless local area network (wireless LAN) and a cellular carrier network, the system comprising:

• a fixed radio terminal configured to communicate with the cellular carrier network and to emulate a mobile terminal on the cellular carrier network;
• and
• a gateway configured to:
• receive a registration message from the mobile terminal via the wireless LAN,
• register the mobile terminal on the cellular carrier network via the fixed radio terminal,
• receive a call from the cellular carrier network via the fixed radio terminal, and
• route the received call to the mobile terminal over the wireless local area network
• by calling a telephone number of the mobile terminal when the received call involves a party in a given network.

A system for managing calls between a wireless local area network and a cellular carrier network, the system comprising:

• a mobile terminal capable of communicating over the wireless local area network and the cellular carrier network;
• and
• a gateway that registers and emulates the mobile terminal on the cellular carrier network when the mobile terminal is communicating via the wireless local area network, the calls from the cellular carrier network being received via a fixed radio terminal of the gateway, the gateway configured to route calls received from the cellular carrier network to the mobile terminal over the wireless local area network;
• wherein the mobile terminal is configured to be assigned a telephone number for the cellular carrier network and a telephone number for a private branch exchange and calls placed to the telephone number of the cellular carrier network are received by the fixed radio terminal of the gateway and routed to the mobile terminal via the wireless local area network when the mobile terminal is on the wireless local area network and calls placed to the telephone number of the private branch exchange are received by the gateway and routed to the mobile terminal via the wireless local area network when the mobile terminal is on the wireless local area network;
• wherein the mobile terminal attempts to register with the wireless local area network and only registers with the cellular carrier network if registration with the wireless local area network is unsuccessful;
• and
• wherein if a call is placed to the telephone number of the private branch exchange while the mobile terminal is communicating over the cellular carrier network, then the gateway calls the telephone number of the mobile terminal on the cellular carrier network and routes the call to the mobile terminal through the cellular carrier network.

A method, comprising:

• registering, at a gateway, a mobile terminal via a wireless local area network (LAN);
• establishing, at the gateway, a wireless-LAN connection to the mobile terminal via the wireless LAN;
• establishing, at the gateway, a wireless connection with a cellular carrier network on behalf of the mobile terminal;
• receiving, at the gateway, a cellular call intended for the mobile terminal from the cellular carrier network and routing the call to the mobile terminal via the wireless-LAN connection;
• receiving, at the gateway, a handoff request from the mobile terminal;
• and
• responsive to the handoff request, the gateway:
• making a second call to a telephone number of the mobile terminal, and
• receiving the second call on behalf of the mobile terminal.