摘要
声束的连续动态扫描在超声成像、水下目标定位和声呐通信等诸多领域发挥关键作用.传统方法通常依赖于发射装置的机械扫描或有源相控阵的波束整形来实时调控声束的空间指向性,存在成本高、尺寸大、主动控制系统复杂而精准操控困难等问题.本文提出并构建了一种基于无源声学超表面的紧凑型静态声呐器件,无需主动控制和机械移动,仅在单一声源的作用下即可实现声束的动态扫描操控.这种新型声呐器件由具有深度亚波长厚度的二值化振幅编码单元组合而成,能够将单一声源发射的梳状频率谱转化为具有相同频率和空间间隔的声焦点阵列,从而引入频率梯度这一新的声波操控自由度,并通过时空声干涉效应产生可连续旋转的动态扫描声束.实验结果验证了所设计超构声呐的高速、宽角度声束扫描性能.此外,通过与传统的相位梯度调控技术结合,该机制还可以对扫描声束的空间形态进行任意的调节.这种基于静态无源超构声呐的声束动态扫描机制为声波的时空调控开辟了新的研究范式,并有望在水下对抗、超声诊疗等重要领域产生实际应用价值.
作者
刘京京
王未
赵澄宇
周永强
张晗
梁彬
仇成伟
程建春
Jingjing Liu;Wei Wang;Chengyu Zhao;Yongqiang Zhou;Han Zhang;Bin Liang;Cheng-Wei Qiu;Jian-Chun Cheng(Key Laboratory of Modern Acoustics(Ministry of Education),Institute of Acoustics,Department of Physics,Collaborative Innovation Center of Advanced Microstructures,Nanjing University,Nanjing 210093,China;Department of Electrical and Computer Engineering,National University of Singapore,Singapore 117583,Singapore;Key Laboratory of Noise and Vibration,Institute of Acoustics,Chinese Academy of Sciences,Beijing 100190,China)
基金
supported by the National Key R&D Program of China(2022YFA1404402 and 2017YFA0303700)
the National Natural Science Foundation of China(11634006 and 12174190)
High-Performance Computing Center of Collaborative Innovation Center of Advanced Microstructures
a project funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions。
