Measurement of frequency of nonsinusoidal signals
L.G. Grainger, K.E. Bolinger · 2002
A method is presented which allows the fundamental frequency of a signal to be accurately obtained from the digital measurement of a signal of an unknown frequency. The method uses a long window time to measure samples. The two largest spectra in the vicinity of the frequency of interest are obtained, and an Sa curve is fitted to the magnitude of the two spectra to interpolate the actual frequency and magnitude.