用信号分析技术检测材料的声速和衰减

Measurements of Material''''s Acoustic Velocity and Attenuation by Signal Analysis

关键词:  快速傅氏变换 声速 衰减 信号分析 传递函数

Key words:  fast Fourier transform,transfer function,velocity,attenuation,quality factor Q

摘要:

用快速傅氏变换（FFT）技术进行超声回波信号体魄分析，以回波传递函数导出与声速和衰减有关的频域方程；用频谱比方法测量材料的衰减品质因素Q值，并与脉冲法所得结果进行比较。

Abstract:

In this paper, the frequency domain equations were deduced from the echo transfer function by the analysis of echo signals with fast Fourier transform(FFT) technology. The material's quality attenuation value Q were measured with frequency spectrum ratio method. Experiment methods, related instruments were also introduced. Examples of measurements were given and the results were compared with those of pulse method.