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. 

在超声换能器激励和接收过程中应用脉冲压缩技术,可以有效提高系统信噪比和检测精度。简要介绍了脉冲压缩技术的原理,分析了脉冲压缩技术中关键参数对回波主瓣宽度、峰值和回波距离分辨能力的影响;对多种不同频带的超声换能器进行了验证性试验。理论分析和试验结果表明,宽带换能器有较好的脉冲压缩性能;在非金属复合材料超声检测中应用脉冲压缩技术可大幅提高信噪比和缺陷分辨能力。

脉冲压缩技术, 超声换能器, 无损检测, 复合材料