Patent ID: 8781481

Claim:
A communication apparatus wirelessly connected to a plurality of networks to handle a call to and from one of the networks, the apparatus comprising: a plurality of interface units each of which includes a front end unit that transmits and receives electric waves and a base band unit that processes call transmission and reception information for the corresponding front end unit, and each of the interface units is associated with a corresponding network of the plurality of the networks; a power source that separately supplies power to the front end units and the base band units of the plurality of interface units, wherein the call is handled by a first interface unit of the plurality of interfaces units; a controlling unit configured to: control the power source to supply power to each of the front end unit periodically to enable the controlling unit detect and evaluate field intensity for each of the front end units using predetermined criteria; connect the power source to a base band unit of a selected interface unit that is different than the first interface unit that handles the call based on a evaluation result of the field intensity to designate the selected interface unit function as a new call destination interface for incoming call data of the call, and in turn disconnect the power source from the remaining base band units of other interface units to suspend the other interface units; and the controlling unit is further configured to facilitate a detour for incoming call data to the new destination interface unit by: via the first network interface unit, sending detour information for the call to the network associated with the first network interface unit prior to the first network interface unit being powered off, wherein the detour information comprises the selected network interface unit's destination address that is configured to cause the network to detour future incoming call data to the selected network interface unit.