期刊名称:International Journal of Signal Processing, Image Processing and Pattern Recognition
印刷版ISSN:2005-4254
出版年度:2014
卷号:7
期号:5
页码:207-216
DOI:10.14257/ijsip.2014.7.5.18
出版社:SERSC
摘要:A new algorithm is developed to detect cardiac cycle's systolic phase from the underwater construction workersDopplerultrasound signal. The method is on the basis of empirical mode decomposition (EMD), in combination with the discrete Hilbert transform (DHT). The EMD combined with DHT constitutes the Hilbert spectrum (HS) which is a fine-resolution time-frequency-energy representation of a nonstationary signal. Here EMD is used to calculate the intrinsic mode functions (IMFs), and thenthe DHT is employed to the IMFs to obtain three instantaneous components- frequency, amplitude and phase. Therefore, the HS is constructed from the normalized instantaneous frequencies and weighted sum of instantaneous amplitudes of the IMFs at the frequency bins. A new representation and interpretation of high graded signal is given to the time-frequency-energy distribution using HS. Finally systolic phase detection performance is evaluated in terms of sensitivity and positive predictivity
关键词:Systolic phase; Empirical mode decomposition; Hilbert spectrum; ; Instantaneous frequency