A Method for Calculating Bottom Backscattering Strength Using Omnidirectional Projector and Omnidirectional Hydrophone  

作　　者：YU Kaiben YU Shengqi LIU Baohua LIU Zhongchen YANG Zhiguo KAN Guangming ZONG Le 

机构地区：[1]College of Marine Geo-Sciences, Ocean University of China [2]National Deep Sea Center,State Oceanic Administration [3]Laboratory for Marine Geology and Environment, Pilot National Laboratory for Marine Science and Technology (Qingdao) [4]Key Laboratory of Marine Sedimentology and Environmental Geology, First Institute of Oceanography

出　　处：《Journal of Ocean University of China》2019年第2期358-364,共7页中国海洋大学学报（英文版）

基　　金：supported in part by the National Natural Science Foundation of China (Nos. 41606081, 4152 7809, and 41330965);in part by the Opening Fund of Pilot National Laboratory for Marine Science and Technology (Qingdao) (No. QNLM2016ORP0209);in part by the Taishan Scholar Project Funding (No. tspd20161007)

摘　　要：A method of obtaining bottom backscattering strength by employing an omnidirectional projector and omnidirectional hydrophone is proposed. The backscattering strength is extracted from monostatic backscattering data. The method was adopted in an experiment conducted in the South Yellow Sea of China. The seafloor surface was relatively smooth and covered by a small quantity of shell fragments, as observed through a digital camera system. Sampling data showed that the main component of the sediment at this experimental site was fine sand. In this paper, we detail the calculation method. Preliminary results of backscattering strength as a function of grazing angle(20?–70?) in the frequency range of 6–24 kHz are presented. The measured backscattering strength increased with the grazing angle and changed more rapidly at large grazing angles(60?–70?). A comparison of the data at different frequencies reveals that the measured backscattering strength substantially rises with the increase of acoustic frequency. A fitting curve of Lambert's law against the measured data shows that the backscattering strength deviates from Lambert's law at large grazing angles.A method of obtaining bottom backscattering strength by employing an omnidirectional projector and omnidirectional hydrophone is proposed. The backscattering strength is extracted from monostatic backscattering data. The method was adopted in an experiment conducted in the South Yellow Sea of China. The seafloor surface was relatively smooth and covered by a small quantity of shell fragments, as observed through a digital camera system. Sampling data showed that the main component of the sediment at this experimental site was fine sand. In this paper, we detail the calculation method. Preliminary results of backscattering strength as a function of grazing angle(20?–70?) in the frequency range of 6–24 kHz are presented. The measured backscattering strength increased with the grazing angle and changed more rapidly at large grazing angles(60?–70?). A comparison of the data at different frequencies reveals that the measured backscattering strength substantially rises with the increase of acoustic frequency. A fitting curve of Lambert's law against the measured data shows that the backscattering strength deviates from Lambert's law at large grazing angles.

关 键 词：acoustic scattering BOTTOM BACKSCATTERING STRENGTH fine sand Lambert’s law 

分 类 号：P[天文地球]