Accurate Digital Synthesis of Sinewaves

This paper discusses the digital synthesis of spectrally pure sinusoidal signals. A modified Sigma-Delta topology consisting of a digital-to-analog converter (DAC), an analog-to-digital converter (ADC), and an analog filter is adopted to efficiently estimate and compensate the DAC nonidealities while desensitizing the system to those of the remaining elements. The proposed correction procedure was implemented on a digital signal processing board equipped with general-purpose data converters. It is shown that the technique can improve the spurious-free dynamic range of the generated signals without requiring high-performance measurement equipment.