Abstract: The reflection coefficient is one of the most important acoustic parameters of materials. In order to measure it in water tank, a method based on pulse compression technique was proposed to extrct the directive and reflective waves from the received compressing signal. This method can overcome unavoidable multi-path disturbance in experiments and easily obtain the reflection coefficient at different frequencies in the measured frequency band. That is, the wide-band measurement for reflection coefficient was realized. The method was verified through simulation. Further more, the experiment results in water tank for an aluminum plate in the frequency range of 30-40 kHz were given also. Comparison of experimental results with theoretical value shows that, although the experiment curve exhibits some deviation and fluctuation, a more accurate result would be obtained by increasing the frequency band of transmitting signal to improve the compression effect or applying appropriate window functions to suppress the level of side lobes.

Key words: acoustics, pulse compression technique, reflection coefficient, wide-band, multi-path disturbance