• Sideband Lock SCPDM Modem for Simultaneous Voice and Data Communications

      Harris, Konstantine W.; Udalov, Sergei; Magnavox; Axiomatix (International Foundation for Telemetering, 1977-10)
      A modem technique for simultaneous transmission of voice and digital data is presented. The salient feature of this technique is the use of quadrature carrier multiplexing of a suppressed clock pulse duration modulation (SCPDM) signal with a biphase NRZ data stream. A novel method for separating the voice and data components at the receiver is described. Data bit error rate and voice intelligibility test results are presented and discussed.