Evaluation of an alternatively designed digital phase angle standard

A phase reference source, that uses a direct digital frequency synthesizer as a digital sine sample generator, was designed and a prototype was built. In this paper, output phase angle deviations are under investigation, especially the circumstances at which they occur. It is explained how the experimental verification of the findings, previously obtained via theoretical analysis and computer simulations, was performed on the prototype. A particular measurement setup is described, utilizing a phase meter and degraded digital-to-analog converters. It was introduced to experimentally evaluate the conditions at which the deviations become visible. Measurement results are presented to confirm the findings regarding the phase modulation intensity dependencies.