Applying sub-band energy extraction to noise cancellation of ultrasonic NDT signal |
| |
| Authors: | Qi Zhang Pei-wen Que Wei Liang |
| |
| Institution: | Institute of Automation Detection, Shanghai Jiao Tong University, Shanghai 200240, China |
| |
| Abstract: | In ultrasonic non-destructive tests,the echo signal at the flaw is highly complex due to the interference of multiple echoes with random amplitudes and phases,and is disturbed by all kinds of noises,such as thermal noise,digitalization noise,and structure noise.In this paper,the ultrasonic signal was decomposed by empirical mode decomposition (EMD) to obtain the intrinsic mode function (IMF) components according to ultrasonic defect echo signals occuring at the corresponding time,and the energy of the ultrasonic signal was concentrated.The IMF component selection criterion based on sub-band energy extraction was proposed to extract the ultrasonic signal component accurately and automatically from IMF components.When the selected IMF components were filtered by a band pass filter,the signal-to-noise ratio (SNR) was enhanced greatly. |
| |
| Keywords: | Empirical mode decomposition (EMD) Signal-to-noise ratio (SNR) De-noising Non-destructive testing (NDT) Intrinsic mode function (IMF) |
| 本文献已被 维普 万方数据 SpringerLink 等数据库收录！ |
|
