A power-saving device for a universal serial bus modem (USB Modem) apparatus is disclosed, which comprises: a personal computer and a USB modem apparatus.

The modem model gives performance data for the selected modem.

When data is sent from a first analog modem (12a) to a second analog modem (12b), a user calls a first digital modem (26a) in the network.

Next, the first digital modem (26a) establishes a connection with a second digital modem (26b).

The calling modem (M) is operable to transmit a modem connection selection signal for selecting a high speed modem connection or a low speed modem connection.

A data call state of the second modem is determined by the first modem.

The apparatus comprises a data interface, a novel modem controller and a modem engine.

Communication with the server is handed over (622) from the cellular modem to the non-cellular modem.

Whenever there is overlap, the lower priority modem will pre-empt the higher priority modem.

A data call state of the first modem is determined by the second modem.

A modem operable to communicate information from a communications link to a host using a universal serial bus includes a modem memory operable to store a plurality of ATM cells.

The present application provides a variety of exemplary embodiments, such as modem systems, modem devices, modem connectors, host connectors, communication systems and communication cards.

Together, the PCMCIA-based radio transceiver and the baseband modem realize a wireless modem.

Each downhole modem communicates with the remote modem using a unique set of frequency subchannels.

In some embodiments, once a modem call is detected, the modem call is terminated.