关键词: 混沌信号, 局部投影, 提升小波, 奇异谱分析, 降噪

Abstract: According to the different characteristics of signals and Gaussian noises, a noise reduction method is proposed based on local projection and lifting wavelet for chaotic signals. Lifting wavelet transform is used to obtain the approximate coefficient, and the phase space of which is reconstructed. It is compared to the phase space of the observed chaotic signals in order to select the local neighborhood of the local projection. Singular Spectrum Analysis（SSA） is combined in the local neighborhood, which uses the main components representing the attractors to reconstruct the chaotic signals. The chaotic time series generated by Lorenz model and monthly sunspot are respectively applied for simulation analysis. The numerical experiment results confirm the effect of the method raised for noise reduction of the observed chaotic signals.

Key words: chaotic signals, local projection, lifting wavelet, Singular Spectrum Analysis（SSA）, noise reduction