文献类型：期刊文献

中文题名：拓展的衍射CT技术反演多孔性海底声学参数

英文题名：Extended Diffraction CT Technique for Inversion of Acoustic Parameters of Porous Seabed

作者：张培珍[1];莫秉戈[1];王斌[2]

机构：[1]广东海洋大学电子与信息工程学院,广东湛江524088;[2]上海交通大学高新船舶与深海开发装备协同创新中心海洋工程国家重点实验室,上海200240

年份：2019

卷号：49

期号：6

起止页码：1788

中文期刊名：吉林大学学报（地球科学版）

外文期刊名：Journal of Jilin University：Earth Science Edition

收录：CSTPCD、、北大核心2017、Scopus、CSCD2019_2020、北大核心、CSCD

基金：国家自然科学基金项目(11774229);广东省教育科学规划课题(2017GXJK066)~~

语种：中文

中文关键词：拓展的衍射CT;收发分置;多孔性介质;四参数生成法

外文关键词：diffraction CT;bistatic system;porous sediments;quartet structure generation set(QSGS)

中文摘要：多孔性海底沉积层的声速、密度、孔隙结构等声学参数是描述海底地质的重要信息,也是声场数值预报、沿岸工程建设地点选择等工程应用中所必须的参数。本文从海底后向半平面不完全投影的散射特性出发,拓展医学上的衍射CT技术,重新推导出收发分置测试系统目标散射强度和相关图像剖面频谱样本的关系式。运用随机生长四参数生成法构建声场图像模型,通过收发分置散射声场的有限稀疏样本,完成单一方向入射线性调频波条件下的剖面图像信息反演验证,得出影响声学参数精度的调频波频率间隔和测量方向数,进一步反演多孔性海底沉积层的孔隙度和平均阻抗指数。与基于网格剖分的数值计算方法相比,本文方法计算效率提高约两个数量级。

外文摘要：Acoustic parameters such as sound velocity,density,and porous structure of seafloor sediments are important for describing seabed,and are necessary for engineering application in sound field numerical prediction and coastal engineering.Based on the backscattering characteristics of the seabed,we extended the diffraction CT technique and re-deduced the relationship between the target scattering intensity and the relevant image spectral sample of the bistatic system.Quartet structure generation set is used to construct the image model of the sound field.When LFM wave is incident from a single direction,the image inversion is retrieved by using the finite sparse sample of the bistatic sound field.The frequency interval and direction number,which affect the acoustic parameter accuracy,are obtained.The porosity and mean impedance indices of sediments are further inversed.Compared with the classical numerical calculation method,the computational efficiency of this method is increased by about two orders of magnitude.