浅海起伏海底环境下的声传播

起伏海底对浅海声传播有着极大影响。文章利用一次东海夏季水文数据，结合蒙特卡洛方法统计分析了浅海长距离起伏海底环境下的声场特性，并利用射线模型分析了海底起伏对声场不确定性影响的机理。结果表明，高频声波对海底起伏的变化更为敏感，传播损失的概率分布更为分散。负跃层环境下，当声源位于跃层下方时，起伏海底对位于跃层下方接收点的声传播影响更为明显。等温层环境下，起伏海底对声传播的影响相比于跃层环境影响更小。起伏海底的倾斜度越大，声传播损失越大。对于相同倾斜度的起伏海底，相对起伏的大小，即起伏海底高度与海深的比值，比起伏周期的变化对声传播的影响更大。

Sound propagation in shallow water with undulating bottom

The undulated bottom in shallow water has a significant effect on sound propagation. Based on the summer hydrological data in the East China Sea, the sound field characteristics in long-distance undulated bottom environment with random bottom roughness are analyzed by using the Monte Carlo method, and the range-dependent propagation mechanism is analyzed by using the ray model. Numerical simulations indicate that the high-frequency sound wave is more sensitive to the bottom roughness, and the probability distribution of transmission loss (TL) is more dispersed. In the negative thermocline environment, when the source locates below the thermocline, the effect of undulated bottom on sound propagation is more significant for the receiver located below the thermocline. In the isothermal environment, the undulated bottom has less influence on sound propagation than in the thermocline environment. And, the greater the inclination of the undulating seabed, the greater the acoustic transmission loss will be. For the same inclination, the relative undulation, namely the ratio of undulated height to water depth, has the greater influence on sound propagation than the change in the length of an undulation cycle.