A Method for Calculating Total Harmonic Distortion of Digital Sinusoidal Waveform

A digital sinusoidal waveform is defined as a periodic waveform whose amplitude and time can be quantified. How do the bit number N of Digital-to-Analog Converter (DAC) and the number M of discrete points in one period influence the Total Harmonic Distortion (THD) of the sinusoidal wave synthesized by digital waveforms? We propose in this paper a theoretical formula representing the relation of THD, M and N on the basis of time-domain analysis and give the calculation results and the experimental data. The novel method presented in this paper can also be applied to harmonic analysis.