小掠射角下高斯谱粗糙海面反射损失建模

在散射能量基本为前向散射且集中在“镜面反射”方向的情况下,粗糙海面反射损失建模是声呐信号传播建模必不可少的一部分,尤其对于中远距离下浅海或者存在表面声道的水声环境,小掠射角(10°以内)下的粗糙海面反射损失建模尤为重要。首先基于高斯谱粗糙海面模型,通过高海况下的声传播试验数据处理分析了粗糙海面边界条件下的Ramsurf声传播模型的有效性,进而以Ramsurf声传播模型为基准,在小掠射角下,比较分析了Kirchhoff近似(KA)海面反射损失模型和小斜率近似(SSA)海面反射损失模型,数值计算结果表明,在小掠射角下SSA海面反射损失模型与Ramsurf计算结果较为吻合,是比较精确的海面反射损失模型。 

Modeling reflection loss of the Gaussian rough ocean surface at small incidence angles

Modeling the acoustic reflection loss of the rough ocean surface is a necessary component of a sonar trans- mission model when the scattering field is mainly forward scattering and focuses on the specular direction. To modeling the reflection loss at small angles is of great significance for acoustic field predictions at medium-to-long ranges,especially for shallow oceans or oceans with a surface duct. Firstly, based on the rough ocean surface of Gaussian spectrum, the validity of Ramsurf acoustic propagation model under rough surface conditions is demonstrated through comparison with the propagation data in high state. Moreover, using the modified PE code——Ramsurf as a benchmark, Kirchhoff Approximation (KA) Reflection Loss (RL) model and Small Slope Approximation (SSA) RL model are compared and analyzed. The numerical simulation implies that the SSA model and the results computed by Ramsurf match well. The SSA model is an accurate RL model.