深海本地界面混响平均强度模型与规律分析

为揭示深海多途传播效应及界面参数对本地界面混响强度的影响规律,将界面混响表述为不同多途混响衰落过程的非相干叠加结果,并结合界面散射的若干物理机制,建立了以海面海底物理参数为变量的混响强度模型.通过数值仿真和理论分析研究了不同多途混响强度的衰落特性、到达角的空间分布及部分物理参数对混响强度的影响,并利用南海海盆(典型泥质海底)实验数据对模型有效性进行验证.仿真结果表明,界面混响强度随时间变化呈现多峰结构,峰值时间与多途混响的到达时间分布一致。声源与接收器均位于近海面处时,首峰的峰值强度及其衰落过程由海面风速决定,其它峰的峰值强度由海面海底参数共同决定,但其衰落过程主要受到底质参数的影响. 

Modeling and analysis of monostatic incoherent boundary reverberation intensity in deep water

In order to study the impact of multipath propagation in deep water and the boundary characteristics on the attenuation of monostatic boundary reverberation,the boundary reverberation intensity is described as the incoherent sum of reverberation attenuation in different paths.The parameterized multipath reverberation intensity model based on scattering theory of physical mechanism is established.Simulations and theoretical analysis are made to study the attenuation of multipath reverberation intensity,the distribution of multipath reverberation arrival angles and the impact of physical parameters on reverberation intensity.The validity of model is verified using experimental data in the south China sea basin(typical mud bottom).The simulation results show that the attenuation of boundary reverberation presents a multi-peak structure and the time that these peaks appear is in agreement with the arrival time distribution of multipath reverberation.When the source and receiver are both near the surface,the intensity of first peak and its attenuation process are determined by wind speed.The intensity of other peaks is determined by the characteristics of both bottom and surface,while the attenuation process is determined mainly by the parameters of bottom.