海底密度梯度对底回波信号空间相关特性的影响研究

研究了海底表层沉积物的垂直密度梯度对底回波空间相关特性强度的影响。底回波散射截面与空间相关特性间的关系为:随入射角的增大,回波散射截面下降得越快,底回波空间相关特性越强。因此,将密度-深度模型引入海底高频回波模型进行回波仿真,计算回波的空间相关函数,通过分析密度梯度对底回波散射截面大小的影响,考察其对底回波空间相关特性强度的影响。从仿真分析结果可以看出,海底表层沉积物密度梯度对空间相关特性的影响较为显著,随着密度梯度的增大,回波散射截面变大且随入射角的增大下降趋势变快,空间相关半径变长,空间相关特性变强。 

The effect of a layer of varying density on spatial correlation of sea-bottom backscattering signal

The research is about the effect of a layer of varying density of seabed sediments on spatial correlation of sea-bottom backscattering.The relationship between scattering cross section and spatial correlation is as the incident angle increases,backscattering cross section decreases quickly,the spatial correlation becomes stronger.Therefore,the seafloor density-depth profile is introduced into high-frequency backscattering echo model,which is used to simulate seabottom backscattering and calculate the spatial correlation.The influence of the density gradient on spatial correlation of sea-bottom backscattering is investigated by analyzing the relations between vertical gradient of density and the scattering cross section.As can be seen from the simulation results,the impact of the density gradient on the spatial correlation is found to be more significant.While the density gradient increases,the scattering cross-section broadens and decreases more quickly as the incident angle increases,the radius of the spatial correlation broadens and the spatial correlation becomes stronger.