1887

Abstract

Summary

There are a lot of methods for the computation of the attenuation including the time-domain methods and frequency-domain methods. The frequency-domain method is widely used at the present stage due to the strong adaptability and stability of the frequency-domain method, including spectral ratio method, the frequency shift method, peak frequency shift method. All these three methods are affected by the windowing effects, that is, the type of window and the length of window. The windowing effects affect the stability and accuracy of the estimation of Q value. Then a new method for the computation of ultrasonic attenuation based on time-frequency analysis is presented. S transform is selected as the time-frequency transform method. The amplitude spectrum of the maximum energy in the time-frequency spectrum is selected to calculate the Q value based on the principle of the spectral ratio method. The feasibility of the method is analyzed through numerical simulation data. In addition, the accuracy and stability of this method are analyzed through standard sample and physical models.

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/content/papers/10.3997/2214-4609.201801409
2018-06-11
2024-03-28
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References

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