Research On Noise Suppression Technology Of One-Dimensional Component Ultrasonic Detection Based On Time Reversal

Rod-shaped one-dimensional components in industrial buildings is widely used,which will appear flaws in production process,such components mainly from the role of load-bearing,facing greater pressure,if flaws are easily damaged,causing accidents.The inspection process does not cause damage to the structure,so non-destructive inspection of the rod-shaped components has the advantage.Pole and other rod-shaped components can be divided into pile-type components and steel rod-type components,depend on the material the project mainly uses ultrasonic detection of non-destructive testing of the rod-shaped components.Research shows that multi-path effect and multi-modal effect of ultrasonic wave can distort the detection signal and In the actual detection process there are various of noise,which make it difficult to detect the signal.The time reversal method for signal detection is researched,which can focus the signal and suppress distortion of the signal based on,so as to improve the detection effect.The ultrasonic signal focusing model based on the time reversal method is established.The simulation results show that the time-law conversion algorithm can restrain the noise of the signal.Because of multi-path effect and noise interference,the damage signal will be difficult to distinguish and the damage signal will be submerged.Even if the signal is decomposed by wavelet packet,the damage signal is still difficult to distinguish,and the detection's signal to noise ratio is reduced,reducing the quality of the signal detection system.In view of the above problems,a time-reversal algorithm based on wavelet analysis is proposed,that is,Wavelet threshold noise suppression,wavelet decomposition and time-reversal simulation re-simulation experiments are carried out on the measured pile foundation ultrasonic testing signal.The results show that this method can suppress the detection signal,the Singularity of the signal is easier to observe,and more conducive to the location of the damage signal.It can separate and focus the damage signal from the detection signal,to improve the SNR ratio of the detection system thus,increases signal-to-noise ratio by an average of 9.4dB,improve the quality of the monitoring system.In order to solve the problem of noise interference in pile foundation testing,the effect of time reversal algorithm on different noise suppression is studied.The experimental results show that the time reversal algorithm has the ability of suppressing noise,and there is ability of suppression for different types of noise,during ultrasonic propagation In the process,both the multi-path effect and the multi-modal effect make the signal distortion more serious.A time-reversal algorithm based on multi-path effect and multi-modal effect is proposed and the simulation experiment is carried out.The results show that the algorithm can be more effectively to suppress the multi-path effect and multi-modal effect of the signal,suppressing the system noise and improving the signal-to-noise ratio at the receiving end of the signal detection system effectively,increasing signal-to-noise ratio by an average of 20.8dB.In order to further improve the signal-to-noise ratio of the system and improve the focusing effect of the signal,the noise suppression algorithm based on channel characteristics is proposed.This algorithm can optimize the detection signal and improve the system's ability to suppress noise and increase signal-to-noise ratio by an average of 22.3dB.