QM/PSK Voice/Data Modem

3587438PDFTech ReportDOT-TSC-FAA-76-05FAA-RD-76-63DOT-TSC-631ModemsModulation (Communications)Voice communicationUnited States. Federal Aviation AdministrationLerner, T.McChesney, J.John A. Volpe National Transportation Systems Center (U.S.)NTL-AVIATION-Air Traffic ControlVolpe National Transportation Systems Center, Technical Reference CenterTwo Quadrature Modulation/Phase Shift Keyed (QM/PSK) Voice/Data Modem systems have been developed as part of the satellite communications hardware for advanced air traffic control systems. These systems consist of a modulator and demodulator unti which provides for one-way communication of voice and/or data signals. The modulator and demodulator unit provides simultaneous transmission of analog voice and digital data signals multiplexed on a single carrier, using quadrature modulation techniques. The modem interfaces with the transmitter/receiver at 70 MHz intermediate frequency. The report contains design theory, circuit descriptions, diagrams, calibration procedures, and laboratory test results