Under-sampling technique for sine wave frequency estimation

An under-sampling technique for estimating fundamental parameters of a sine wave is proposed. An algorithm for finding excess factor, direction of sampling, and final estimates including signal frequency, amplitude, initial phase angle and magnitude of pedestal, is shown in detail. The technique combined with non-uniform sampling and the Prony method is evaluated by numerical experiments. The technique gives accuracy on each estimate, showing higher precision especially on higher frequency up to an extraordinary higher limit. Thus, the technique enables us to utilize slower A/D converters for higher frequency measurement, or to achieve extremely high frequency measurement with using faster A/D converters.