Multi-modal handy phone

Claim 1

A radio telephone system having a multi-modal handy phone accessible to a plurality of radio telephone networks, said multi-modal handy phone comprising: a plurality of radio modules, each of said radio modules adapted to access a corresponding one of the plurality of radio telephone networks; a communication monitor monitoring communication quality between said multi-modal handy phone and each of the plurality of radio telephone networks, the communication monitor detecting a degradation in communication quality and providing a signal for controlling a changeover to an alternative radio module in the event of a degradation in communication quality; a changeover unit selecting one of the plurality of radio modules in response to the signal from the communication monitor; a telephone number register storing a telephone number of the other party with which said multi-modal handy phone is in communication, said telephone number of the other party being transmitted from one of the plurality of radio telephone networks when the multi-modal handy phone is called through said one of the plurality of radio telephone networks; a calling unit calling a telephone number registered in said telephone number register by way of one of said plurality of radio modules selected by said changeover unit, said calling unit being controlled by said changeover unit to automatically call the telephone number registered in the telephone number register through one of said radio modules when the communication monitor determines that a presently used one of the radio telephone networks has become unavailable; and a user interface unit interfacing signals to be sent and received through said one of said plurality of radio modules selected by said changeover unit with a user.