Abstract:There are physical meanings for taking instantaneous parameters of signal by Hilbert transform, which is not always true for any signals. This approach requires analyzed signals being narrow band or stationary and sensitive to noises. But the practical seismic signals are non-stationary and noisy, if taking instantaneous parameters by Hilbert transform without consideration in practical application, the yielded instantaneous parameters will be lack of physical meanings or distortion. Hilbert-Huang transform is new approach for analyzing non-stationary and non-linear signals, which first carries out empirical mode decomposition (EMD) for signals, forming sum of limited intrinsic mode functions (IMF), then, the time-frequency spectrum is taken for IMF by Hilbert transform, the yielded time-frequency spectrum has higher resolution in both time and frequency domains. The paper applied Hilbert-Huang transform to take seismic instantaneous parameters, which showed in real cases that feature in different time scale could be obtained by carrying out EMD for seismic sections, and Hilbert spectrum has higher resolution in both time and frequency domains in comparison with traditional time-frequency spectrum; the strong reflection horizons appear more distinctive in first-order IMF instantaneous frequency section than in original instantaneous frequency section.
皮红梅, 刘财, 王典. 利用Hilbert-Huang变换提取地震信号瞬时参数[J]. 石油地球物理勘探, 2007, 42(4): 418-424.
Pi Hong-mei, Liu Cai, Wang Dian. Using Hilbert-Huang transform to pick up instantaneous parameters of seismic signal. OGP, 2007, 42(4): 418-424.