DIGITAL DATA TRANSMISSION SYSTEM MODEM

摘要

DIGITAL DATA TRANSMISSION SYSTEM MODEM A modem for transmission systems providing for simultaneous conventional baseband telephone signaling and digital data transmission on nonloaded telephone wires is disclosed. The modem includes a data transmitter that converts digital data to be transmitted from binary form into F1/F2 FSK form and a receiver that converts received digital data from F3/F4 FSK form into binary form. The modem is designed to be connected between a telephone transmission line and provide simultaneous conversion between binary form and FSK form.