粗晶材料超声检测信号模型及其通过窄带滤波器分析

分离谱处理技术已被用于增强粗晶材料超声检测的缺陷回波信号.在分离谱技术中,宽带超声脉冲回波通过一组窄带滤波器阵列分别进行滤波处理,由于人们尚不清楚该技术是如何有效利用这些滤波器的输出特性进行工作的,使得该技术的各种算法都有性能不够稳健的问题.本文通过构造一粗晶材料超声检测信号模型,进而获得超声信号通过窄带滤波器阵列的输出特性.文中还给出了计算机模拟的结果.

An Ultrasonic Testing Model for Large Grained Materials and Its Output Properties of Narrowband Filter

Split spectrum processing has been proposed for ehnancement of flaw echo in ultrasonic testing of materials with large grains.The split spectrum technique is a method where one wideband ultrasonic pulse echo is filtered through a narrowband filter bank.However,the split spectrum processing algorithms are not robust since it is not clear how the technique use the filter outputs available.In this paper,a signal model of ultrasonic testing for large grained materials is developed.Using this model,the outcoming ultrasonic signal of a narrowband filter bank is obtained.Finally,some simulation resutls are illustrated.