基于多重相关法的涡流阵列传感器信号处理研究

Study of signal processing of eddy current array sensor based on multi-layer correlation method

分析了多重相关法的基本原理,搭建了用于测试一种平面涡流阵列传感器提离效应的实验平台,并采用多重相关法对其多通道含噪声输出信号进行消噪处理,提取出多通道输出信号同激励输入信号幅值比和相位差信息,并分析了提离距离对输出信号的影响。研究结果表明:将多重相关法应用于该平面涡流阵列传感器的多通道含噪声输出信号的消噪处理效果明显,该算法大大提高弱强度、强背景噪声信号的信噪比;随提离距离的增加,阵列传感器各通道输出信号同激励输入信号的幅值比单调递增,而相位差基本保持不变,这些规律为该传感器的进一步研究与应用提供了参考。

The basic principles of multi-layer correlation method are analyzed. An experimental platform for testing the lift-off effect of planar eddy current array sensor is established, and the noised output signals of eddy current array sensor are denoised using multi-layer correlation method, which is followed by extracting of amplitude ratio and phase difference information between the output signal and pumping input signal. Besides the influences of lift-off on output characteristics are also considered. The result shows that multi-layer correlation method is applicable in denosing of the output signal of eddy current array sensor, and the signal-to-noise ratio（SNR） is substantially improved. As the lift-off distance increases, the amplitude ratios between the output signal and pumping input signal are monotonically increased, while the phase differences remain unchanged. These rules provide a reference for further research and application of the sensor.