超声探测弱信号提取方法

为了在超声检测中排除噪声干扰，从强噪声背景中提取弱回波信号，利用小波变换技术从超声探测信号中提取弱缺陷回波信号，建立了超声缺陷回波的数学模型，并进行了仿真实验，其特有的“变焦距”特性使得小波分析在时域和频域中具有良好的分析能力。结果表明，利用小波变换方法能够很好地抑制噪声，提高信噪比，提取强噪声背景中的弱回波信号，且该方法原理简单，易于实现，在工程上有较高的应用价值。

Study on Weak Signal Extraction in Ultrasonic Detection

In order to suppress noises and extract weak echoes from signals with high noise background, wavelet transform technology was used for extracting weak flaw echoes from ultrasonic detection signal, and at the same time the mathematical model of ultrasonic detection flaw echoes was established and simulation experiments were done, Test result shows wavelet transform technology could depress noises well, improve signal-to-noise ratio, and extract weak flaw echoes from high noise background effectively.