摘 要:在分析小波变换消噪原理和方法的基础上,针对信噪比较高的信号,进行小波消噪和傅里叶消噪仿真分析。结果表明,采用小波消噪能达到比较理想的效果。但对于信噪比较低的信号,必须采取多种方法相结合,才能取得满意的消噪效果。文章提出了将时域平均法和小波软阀值消噪法相结合和基于相关性分析与小波变换相结合两种方案消噪。通过对这两种方案进行仿真实验,结果表明,这两种方案可以有效地去除信号中的干扰噪声,提高信号的信噪比,取得良好的降噪效果。 关键词:小波变换;时域平均;软阀值;分析;消噪
Abstract: Based on the analysis of the de-noising principles and methods of the wavelet transform,when the signal-to-noise ratio(SNR)of a signal is high,wavelet transform is proved to be an effective method by the simulation analysis after comparing with the wavelet transform and fourier transform in regard signal denoising.But when the SNR is low,it’s must be adopted a combined method with an excellent result.Two combined methods were suggested to reduce the noise in this paper.The combination of time domain average and wavelet softthresholding,the correlation analysis and wavelet transform as well.The results show that the noise can be reduced effectively by bh simulation and experiments. Key Words: Wavelet transform;Time domain average;Soft-thresholding;Analysis;De-noising
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