摘要
水下声信号传播到水面时,由于水和空气的声阻抗差,会激发水表面横向微幅波,其振动信号包含了声源的相关信息。雷达通过目标回波间的相位差来检测目标的微小位移,因此可以利用雷达检测水面微小位移变化获取水面振动信号,进而反演水下声源信息。该文首先分析了水下声传播的衰减特性及水面振动的物理模型,然后基于雷达回波模型对声致水面振动检测进行理论分析,提出了小波-卡尔曼滤波信号检测方法,最后在大型综合消声水池和黄海水域开展了基于太赫兹雷达的声致水面微动信号检测实验。实验结果表明所用太赫兹雷达能够检测声致水面的细微振动,所提算法能有效滤除水面干扰和雷达相位噪声并提取振动信号。实验首次在二级海况下检测到了亚微米级的振动信号,为水-空跨介质信息传输与水下航行器探测提供了依据。
When underwater acoustic signals propagate to the water surface,the acoustic impedance difference between water and air leads to transverse microamplitude waves on the water surface.These waves carry vibration frequencies containing relevant information about the sound source.Radar systems detect the slight displacement of the target through the phase difference between the target echoes;hence,radar systems can be used to detect small displacement changes on the water surface,thereby obtaining the water-surface vibration signal and subsequently inverting the underwater sound source information.In this study,we first analyzed the attenuation characteristics of underwater sound propagation and the physical model of water-surface vibration.Building upon the radar echo model for detecting acoustic water-surface vibration,we proposed a wavelet-Kalman filter signal detection method through theoretical analysis.Lastly,experiments were conducted in the large-scale comprehensive anechoic pool and the Yellow Sea water using terahertz radar for acoustic watersurface micromotion signal detection.The results demonstrate the capability of the terahertz radar to successfully detect acoustic water-surface microvibrations.The proposed method effectively filters water-surface interference and radar phase noise and extracts vibration signals.For the first time,submicron vibration signals were detected under a secondary sea state,providing a foundation for water-space transmedia information transmission and underwater vehicle detection.
作者
邓彬
李韬
汤斌
易俊
王宏强
杨琪
DENG Bin;LI Tao;TANG Bin;YI Jun;WANG Hongqiang;YANG Qi(College of Electronic Science and Technology,National University of Defense Technology,Changsha 410073,China)
出处
《雷达学报（中英文）》
EI
CSCD
北大核心
2023年第4期817-831,共15页
Journal of Radars
基金
国家自然科学基金(61921001,61971427,62035014,62201591)。
关键词
太赫兹雷达
声致水面
微动信号提取
相位测距
小波-卡尔曼滤波
Terahertz radar
Acoustic water surface
Micro-motion signal detection
Phase ranging
Wavelet-Kalman filtering
