浅海相干声场的单参数海底模型建构

海底反射性质在浅海声传播中起着决定性的影响。利用海底反射损失对掠射角的斜率可作为单个参数F dB来描述海底这一前提，对平面波入射液态半无限空间的情况进行推导，提出一种基于简单近似表示反射相位角关系的算法。将单参数F dB以及反射相变作为计算模型的边界条件输入参数，对浅海相干声场进行计算，将适用范围推广到复杂声速和水平变化情况。通过对三种类型海底进行仿真，比较基本参数海底模型及单参数海底模型计算所得传播损失曲线，验证了所提包含反射相变关系的单参数模型的有效性。

Single parameter seabed modeling in shallow water interference field

In shallow ocean, sound transmission is mainly dominated by seafloor reflectivity. Utilizing the prerequisite that the slope of bottom loss versus grazing angle can be considered as a single parameter F_dB to describe sea bottom, the reflection phase angle can be determined via a simple approximation based on the incidence of plane wave to a uniform fluid half-space. The interference field, in which F_dB and reflection phase angle can be inputted to computation models as boundary conditions, is estimated. And the sphere of application is extended to the case of complex sound speed and range-dependent environment. The validity of the single parameter model that includes reflection phase is illustrated by the simulations for three types of seabed examples, in which the transmission losses predicted by basic parameters are compared with those predicted by this simple seabed model.