Research on Ultrasonic Detection of Seabed Oil Pipeline Based on Wavelet Packet De-Noising

It is very important, by analyzing and processing ultrasonic echo signals of seabed oil pipeline, to acquire the effective information. Because of the complicated detection system structure and ultrasound coupler impurity, there are inevitably different noises in echo signals. In order to improve the accuracy of detection, it is very necessary to process ultrasonic echo signals by de-noising. According to characteristics of ultrasonic echo signals, we proposed a de-noising method, based on wavelet packet in this article. With this method, the principle of wavelet packet de-noising and the selection of threshold functions are applied into detecting and de-noising ultrasonic echo signals. The experiment and simulation results show that this de-noising method, by increasing the signal-to-noise ratio, can obviously improve the noise suppression effect and detection accuracy on ultrasonic echo signals of seabed oil pipeline.