The HHT time-frequency power spectrum analysis of the blasting vibration signal

The short-time Fourier transform can not meet the different requirements of the high and low frequency changes of signal and the wavelet transform can be limited by the wavelet base we select.Therefore,we use HHT to analyse the blasting vibration signal through the time-frequency power spectrum.In the EMD,we use the symmetric extending of extreme point to eliminate the effect of endpoint.We use the piecewise cubic Hermite interpolating to eliminate the phenomenon due to the envelope,and adopt the local criterion of sifting termination.For the problem of negative peak in calculating the instantaneous frequency in the traditional Hilbert transform,we adopt the normalized Hilbert and the direct quadrature method to solve.In all the HHT analysis,we use the LabView platform to achieve which can improve computing efficiency and practicality,and we prove that HHT is useful for the analysis of the blasting vibration signal.