Study Of Ultrasonic Inspection Based On Array Signal Processing

Ultrasonic nondestructive testing is an important branch of detection technique. Ultrasonic phased array technology obtains flexible and controllable synthesis beam by phase control of matrix elements of transducer array. It has the following advantages: dynamically focusing ; imaging testing; detecting shape of complex objects ;improving detection sensitivity ,resolution and signal-to-noise ratio and so on .The most important merit is improving detection efficiency , so it becomes the research focus of nondestructive testing . That is why the paper research on the branch.In this paper, first ,we introduce the basic principles of phased array, and research dynamic electronic focus in-depth .Then, using dynamic photoelastic system we study the propagation properties of ultrasonic wave when they encounter obstacles in the solid,and study further in the focus properties of ultrasonic phased array in the solid,so as to lay foundation for the follow-up system design.In the paper, we introduce the structure of ultrasound phased transducer array and choose the material that transducer array used. Then we analyze parameters have effect on performance of transducer; so we select the parameter of transducer according to above analysis. In this paper ,a unique design to achieve a complete 16-channel phased array ultrasonic detection system is designed,as well as the distributed processing system between the lower machine and PC , and we use a kind of signal processing structure --DSP + FPGA on the lower machine (PCI card), which greatly improves the system's capabilities in real-time signal processing, and meet the requirements of high-speed signal processing of the multi-channel, high-capacity data stream.Finally, we verified the system can launch focusing to setpoint with experiment and outbrust echo signal . So the throey has application meaning .