关键词: 短时强干扰, Hilbert-Huang变换, 经验模态分解, 瞬时振幅, 瞬时频率

Abstract: According to the characteristic that short-time strong disturbance in signals can lead to obvious abnormity in instantaneous amplitudes and frequencies, an HHT-based method to eliminate the disturbance is proposed. The signal with short-time strong disturbance is decomposed into a series of Intrinsic Mode Functions（IMF） and a residue by the Empirical Mode Decomposition（EMD）. The instantaneous amplitudes and frequencies of each IMF are calculated. In abnormal sections, they are fitted according to the data in normal sections, replacing the original ones with the fitted data. A new set of IMF is reconstructed by using the processed instantaneous amplitudes and frequencies. For the residue, abnormal fluctuations are directly removed. A new signal with the short-time strong disturbance eliminated is reconstructed by superposing all the new IMF and the residue. Results of numerical simulation and measured signal verify the feasibility of the method.

Key words: short-time strong disturbance, Hilbert-Huang transform, empirical mode decomposition, instantaneous amplitude, instantaneous frequency