Digital Time-Domain Technique for Generating Serial MSK Signal

A digital time-domain technique for the generation of serial minimum shift keying (SMSK) signal is described. Two pairs of synchronized antiphase sinusoidal waveforms, representing the MARK and SPACE signals, are obtained through filtering of digitally generated square waveforms. A synchronous sequential circuit then appropriately multiplexes the four sinusoids to generate the desired SMSK signal. Phase continuity of the SMSK waveform during symbol transitions is inherently maintained. Design procedure and implementation details of this simple digital SMSK generator has been provided.