一种对缆索无损探伤微弱信号的处理方法

A Weak Signal Process Method of Cable Nondestructive Inspection

摘要: 针对在处理缆索无损探伤微弱信号时，微弱信号信噪比小，无法清晰反映缆索内部微小缺陷的问题。设计了一种通过在准确的时序控制下对微弱信号进行多次采集，并将采集到的信号序列严格按照时间线累加的处理方法。由于信号噪声在时域的分布属于正态分布，即均匀且对称的分布在真实值两侧，经过累加后会互相抵消；而真实信号不属于正态分布，经过多次累加，信号值会被放大，所以通过此种方法在不放大噪声的情况下，能有效地放大真实信号，使得由微弱的内部缺陷而产生的微弱信号能够被清晰地分辨出来，大大提高了无损探伤的准确性。该方法简单，可操作性强，适应范围广，具有较高的推广价值。

Abstract: A method is designed to deal with the problem that the signal-to-noise ratio of the weak signal is small when processing the weak signal of nondestructive inspection of cables, which can’t clearly reflect the tiny defects inside the cables. This method collects the weak signal several times under the accurate timing control and accumulates the collected signal sequence strictly according to the time line. Because the distribution of signal noise in time domain belongs to normal distribution, i.e. uniform and symmetrical distribution on both sides of the real value will cancel each other after accumulating, while the real signal does not belong to normal distribution. After multiple ac-cumulations, the signal value will be amplified. By this method, the real signal can be amplified ef-fectively besides the noise, so that the weak signal generated by the weak internal defects can be clearly distinguished, and the accuracy of nondestructive inspection is greatly improved. This method is simple, easy to operate and has a wide range of applications, and has high popularization value.