Simulation of quantization errors spectrum for direct digital synthesizer sinusoidal output

Direct digital synthesizers (DDS) have widespread use in modern frequency and signal synthesizers, which require flexible control, fast hopping and high frequency resolution at a low cost of implementation. At the same time, the discrete character of DDS output causes generation of multiple spurious components in spectrum, which can decrease the quality of synthesizers. This paper presents the investigation of quantization errors caused by finite amplitude resolution of DDS. Simulation of spectrum of DDS output oscillation was made considering the amplitude quantization and time sampling. The minimal achievable level of the spurs caused by amplitude quantization depends on the size of the phase accumulator. For a correct estimation of quantization errors to the spectrum of the output oscillation of the DDS, it is advisable to represent them as discrete components.