Simultaneous Transmission of Digital Phase-Shift Keying and of Analog Television Signals

A method for transmission of a 1.544-Mbit/s data channel in a frequency band which is above the baseband of sound and vision signals of color television in FM microwave systems is described. The impact of the interfering video signal on phaseshift keyed (PSK) performance is evaluated. The probability of error as a function of the receiver carrier-to-noise ratio in the data channel for the case of Gaussian noise, sinusoidal interference, and various video test waveform (color bar, stair step, etc.) interference and combinations of these is measured. Analog and also novel digital methods of insertion of the television sound subcarrier signal are described. Data above video (DAVID) transmission measurement results which have been performed on an RCA 6-GHz microwave hop are presented.