Instantaneous Bispectral Analysis of Non-linear and Non-stationary Ship Motion Data

摘要

The instantaneous bispectral analysis was proposed to investigate nonlinear and non-stationary ship responses. The method is based on Time-varying coefficient autoregressive (TVAR) modeling and an extension of the instantaneous power spectral analysis. The proposed method was applied to the time history which indicates the fluctuating skewness, and the peak and its phase angle of bispectra were followed in the time domain to explain the fluctuating skewness. The effectiveness of the instantaneous bispectra was shown for analyzing the transition of skewness of non-linear ship responses.