A compact spectrum constant envelope digital phase modulation

A digital modulation system with compact spectrum and constant envelope is proposed, based on the results of theoretical and experimental studies. This modulation system is suitable for digital mobile communication, which generally is subject to deep and rapid fading. It is characterized with a possibility of practical and stable instrumentation. In the modulator, modulation signal parameters are read out of the memories, by which precise spectrum and waveform can be realized. For the modulator, an orthogonal phase modulation, whose parameters are stable, can be adopted by pertinent parameter design for the modulating signal stored in the memories. The experimental results agree well with the design.