APPLICATION OF THE WIGNER DISTRIBUTION FO R TIME-FREQUENCY ANALYSIS OF NONSTATIONARY SIGNALS

A spectrum analysis of measured data is required in many cases. The mo st used method to obtain a spectrum is the well known Fourier transfor m. However the Fourier transform was found to be unsuitable for analys ing nonstationary signals. In this cases the spectrogram is commonly u sed for spectrum analysis of nonstationary signals. With strong nonsta tionarities also the spectrogram provides some ambiguity in time and f requency. In this paper a method is presented that enables the time - frequency analysis of nonstationary signals with a high rime and frequ ency resolution - the Wigner distribution. Fundamental aspects of the Wigner distribution will be explained and its basic properties are exa mined. The power of this tool is illustrated at some examples.