Real-time high accuracy measurement of multifrequency waveforms

This paper discusses the operating principles and the main characteristics of a digital instrument for multifrequency signal analysis. The instrument provides real-time performance in a frequency range of 5–6 kHz with high measurement accuracy, obtained by combined windowing and interpolation of computed discrete Fourier transform (DFT) coefficients. Its hardware structure and measurement software for real-time operation are thoroughly illustrated and experimental results are given.