De-noising method of blasting vibration signal based on improved EMD
An improved EMD blasting vibration signal noise reduction method is proposed for the problems of endpoint effect and poor denoising effect of EMD algorithm.Firstly,the blasting vibration signal is extended by SSA optimized SVM,and different IMF components are obtained by EMD decomposition,and then the correlation coefficients between the different IMF components and blasting vibration signals are calculated,divided into IMF components containing noise and IMF components containing effective signals,and calibrated by the variance contribution rate.Finally,the wavelet packet is used to reduce the noise of the IMF component containing noise,and the noise-reduced blasting vibration signal is reconstructed.By constructing the simulation signals and the measured signals and using the evaluation indexes,the feasibility of the delayed approach of SSA optimized SVM to suppress the EMD endpoint effect is verified.The noise reduction effect of the improved EMD blasting vibration signal is verified by using the root-mean-square error,signal-to-noise ratio,and wavelet packet energy spectrum of the measured blasting vibration signal as an example.The results show that compared with mirror extension method,the SSA optimization SVM method has the best effect of suppressing the endpoint effect of EMD;compared with CEEMDAN-wavelet thresholding,CEEMDAN and EMD,the improved EMD method has the largest signal-to-noise ratio and the smallest root-mean-square error,and the signal-to-noise ratio is improved by 1.77,4.62 and 1.94 dB,and the energy of high-frequency band of the signal is reduced after the noise reduction of this method,and the energy proportion of middle and low frequency band is improved to different degrees,which indicates that the improved EMD method not only has good noise reduction effect,but also can effectively retain the original signal energy information.
万方数据
维普
