A PCM subcarrier system has been developed which will permit video microwave to carry twenty-four 6 kHz channeIs a long with the normal video signal. The channels may be used directly or split into forty-eight 3 kHz voice channeIs. The subcarrier system uses a differentially coherent quadraphase approach and has a data rate of three megabits.
The paper outlines the frequency requirements of implementing a subcarrier in the presence of video. Then a system block diagram description is given for the channelizing and subcarrier equipment. Performance curves taken from experimental data are given. These include the error rate performance for the system in the presence of differential phase and gain along with thermal noise.