Skip to Main Content
In this paper, we present a technique for a combination of amplitude and phase modulation for digital communication. This technique assumes phase coherence between transmitter and receiver. For purposes of analysis, we also assume baud synchronization. The technique involves the simultaneous and independent amplitude modulation of two carriers of the same frequency which are in quadrature with each other. The demodulation process consists of the separation of the in-phase and quadrature components followed by amplitude detection. This scheme appears to be easier to implement than either the system studied by C. R. Cahn or the system investigated by J. C. Hancock and R. W. Lucky. Furthermore this system is comparable in reliability to the latter scheme.