中文摘要：

海底作为海洋波导的重要边界,其反射系数对声传播起着至关重要的作用.为了快速而准确地获取海底反射系数,提出了一种基于脉冲压缩技术的测量方法,对接收信号进行压缩来提取反射波.该方法不仅可以克服实验过程中经常遇到的多途干扰,而且测量过程简单,可以同时获得测量频带内所有频点的反射系数,即实现了对反射系数的宽带测量.在实验室环境条件下,针对广泛覆盖于大陆架及沿海地区的沙质沉积物反射系数进行了测量,通过20～60 kHz频率范围内窄带和宽带测量结果的比较发现,宽带测量结果在频带边缘存在一定的偏差和起伏,但可以采用增大发射信号带宽提高压缩效果或用适当的窗函数压低旁瓣的方法来得到频率范围更宽、精度更高的测量结果.

英文摘要：

Seafloor plays an important role in acoustic propagation as a significant boundary of ocean waveguide.In order to measure the seafloor reflection coefficient fast and accurately,a method based on pulse compression technique is proposed in this paper,where reflective wave are extracted from the received compressing signal.This method not only can overcome unavoidable multi-path disturbance in experiment,but also can easily obtain the reflection coefficients for different frequencies in measured frequency band at the same time.That is,wide-band measurement for reflection coefficient is realized.The reflection coefficient of sandy sediments that widely cover over continental shelf and littoral regions is measured in laboratory.Through the comparison of narrow and wide band measured results in the firequency range of 20kHz-60kHz,it is found that the latter somewhat exhibits deviation and fluctuation in the edge,but a broader frequency band and 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 levels of side lobes.