[The time-frequency analysis of the heart sound]

The Wigner-Ville distribution, the Choi-Williams distribution, and cone-kernel distribution are three time-frequency distributions. We compared the interference attenuation and time-frequency concentration properties of the three TFDs. The properties were then further investigated by studying the results obtained for a chirp signal. We analysed the heart sounds, nonstationary signals, with the three TFDs. The results indicate that the time-frequency signal analysis methods have high time-frequency resolution. The time-frequency signal analysis techniques may be helpful in unveiling the complex mechanisms of heart sound generation and be used in medical research and clinical diagnosis.