脉冲压缩技术, 超声换能器, 无损检测, 复合材料

The signal-to-noise ratio and testing precision can be effectively improved with the usage of pulse compression technique in the ultrasonic transducer excitation and receiving process. After introducing the basic principles of pulse compression technique, the influences of its key parameters on echo main lobe width, amplitude and distance resolution were analyzed. Experiments were done with transducers of different bandwidths. Theoretical analyses and experimental results indicate that the broadband transducers have a better pulse compression capability. The signal-to-noise ratio and the testing resolution can be greatly improved in ultrasonic testing with the application of pulse compressing technique. 