An improved EMD time-frequency analysis method for rocket vibration signal

According to noise and low frequency redundant problems generated by analyzing non-stationary signal with empirical mode decomposition (EMD) method, this paper proposes an improved EMD method which uses instantaneous frequency weighed average algorithm to eliminate noise component and correlate coefficient significant test to eliminate low redundant components. The improved EMD method which can obtain effective intrinsic mode function (IMF) from investigated signal was applied in simulation signal and rocket vibration signal to analyze time-frequency characteristics. The result indicates that this method can eliminate noise and low frequency redundant component effectively.