A Method of Feature Extraction for BCG Signal Based on Wavelet and Bispectrum

The ballistocardiogram (BCG) is a useful information signal reflecting the state of cardiovascular system. In order to improve the monitoring level of cardiovascular diseases in China, a wavelet-bispectrum analysis method was proposed to extract the characteristic of BCG signal. First, the BCG signal was preprocessed. Then, wavelet decomposition and reconstruction were performed by choosing the appropriate wavelet function and decomposing levels, and the sub-bands were bispectrum analyzed for reconstruction. Finally, the maximum amplitude of slice spectrum and energy of each sub-band of BCG signal were extracted. The results have shown that the method can obtain the high-order time-frequency information in the BCG signal, and has obvious advantage for the non-stationary and non-Gaussian processing of BCG signal, it also provide a reliable basis for the application of BCG signal in clinical diagnosis.