基于PSM算法的激光致声SAFT水下小目标探测方法  

Underwater Small Target Detection Method of Laser-Induced Acoustic SAFT Based on PSM Algorithm

作　　者：赵扬 李鹏[3] 张鹏辉 周志权[1] 白雪 马健[3] Zhao Yang;Li Peng;Zhang Penghui;Zhou Zhiquan;Bai Xue;Ma Jian(School of Information Science and Engineering,Harbin Institute of Technology(Weihai),Weihai 264209,Shandong,China;Weihai City Key Lab of Photoacoustic Testing and Sensing Technology,Weihai 264209,Shandong,China;Laser Institute,Qilu University of Technology(Shandong Academy of Sciences),Jinan 250103,Shandong,China)

机构地区：[1]哈尔滨工业大学(威海)信息科学与工程学院,山东威海264209 [2]威海市智能光声检测与传感技术重点实验室,山东威海264209 [3]齐鲁工业大学(山东省科学院),山东省科学院激光研究所,山东济南250103

出　　处：《中国激光》2022年第9期135-146,共12页Chinese Journal of Lasers

基　　金：哈尔滨工业大学科研创新基金(202006);哈尔滨工业大学青年教师发展基金(202002);山东省重大科技创新工程项目(2020CXGC010705)。

摘　　要：水下目标的有效探测是认知海洋的前提与关键。本文介绍了一种可用于空-水跨介质探测成像的激光致声合成孔径聚焦技术。分别建立激光源阵列中心聚焦及偏转聚焦的有限元仿真模型,进而模拟激光致声合成孔径聚焦探测过程,采用相位迁移算法对模拟的激光致声信号进行探测图像的重构。采用均方误差与峰值信噪比对图像质量进行评价。搭建了空气-水下激光致声探测实验系统,通过分析水中钢球经衍射后的声波能量变化,计算出了其平均能量损失率。利用合成孔径延时叠加波束形成方法实现了声波能量在目标处的汇聚及增强,为水下目标探测提供了一种新的实现途径。Objective Effective detection of the underwater target is essential for the premise and key to understanding the ocean.Meanwhile,the ocean plays a significant role in national defense.The detection technology of a crossing airwater medium provides a new way to detect and communicate between air-based and underwater-based platforms,which is a hot research issue globally.Aiming at the limitation of the high loss for detecting signals caused by the physical interface between air and water,this study combines the synthetic aperture focusing technique(SAFT)and laser-induced acoustic(LIA)for the imaging detection of crossing air-water medium.The simulation calculation,numerical simulation,and experimental research on air-water cross medium detection of photoacoustic signal conversion between a nanosecond pulse laser and a hydrophone were conducted.The LIA-SAFT based on the phase shift migration(PSM)algorithm has the following advantages to realize photoacoustic underwater target detection:1)Laser and acoustic signals can be transmitted remotely in air and water,respectively.2)High source-level sound waves can be generated by increasing the pulse energy.3)Sound signal has characteristics of pulse narrow,wide spectrum,high temporal and spatial resolution.4)As a post-processing method of acoustic signals,SAFT can solve the problems of poor imaging effect and low resolution.5)PSM algorithm can be effectively used to improve the image resolution and quality.Methods This paper investigates LIA-SAFT imaging based on the PSM algorithm.Finite element simulation models of SAFT for center and deflection focusing were established(Fig.8).Then,the simulation of LIA-SAFT was conducted.The influence of water-surface disturbance on amplitude of LIA signal was analyzed for the cases of no disturbance,micro disturbance,and large disturbance of water-surface,respectively.The PSM algorithm was used to reconstruct the detection image of LIA-SAFT(Fig.12).The main procedures of LIA-PSM detection are as follows.First,data analysis software was

关 键 词：遥感 信息处理 激光致声 合成孔径聚焦技术 相位迁移算法 有限元仿真 

分 类 号：TB566[交通运输工程—水声工程]