声轨道角动量水下发射与数据传输实验

研究了声轨道角动量水下发射技术与多路复用的水下数据传输,基于点源理论推导了相控圆周阵列发射声轨道角动量的基本原理,分析了干扰项的阶数成分及干扰项对主项的影响,优化设计了基于Cymbal换能器的阵列样机,阵列样机直径为Φ180 mm,阵元数为10元,工作频率为25 kHz,通过对阵列阵元的相位调控实现了-3至3六阶声轨道角动量的发射,验证了基于相控原理实现不同拓扑荷数声轨道角动量发射的理论。通过利用各阶声轨道角动量的开关状态进行数据编码,进行了基于声轨道角动量多路复用的水下数据传输实验,实验结果表明,不同拓扑荷数的声轨道角动量具有良好的正交性质,可以利用基于声轨道角动量的多路复用技术实现水下数据传输功能。 

Generation of underwater acoustic orbital angular momentum and data transmission

Underwater acoustic communication based on the acoustic orbital angular momentum multiplexing is studied.The principle of acoustic Orbital Angular Momentum (OAM) emitted by the phased arrays is derived based on the point source theory.The order of interference terms and the interference terms to the main terms are analyzed.based on the finite element method,a prototype based on the Cymbal transducer was designed.The diameter of the array prototype is Φ180 mm,the number of array elements is 10 and the working frequency is 25 kHz.By adjusting the phase of the array element,it generates 6 OAM charges from-3 to 3,verifies the theory of OAM with different topological charges based on the phase control.By using the on-off state of each order to encode data,an underwater data transmission experiment is carried out.The experimental results show that the acoustic OAM with different topological charges has good orthogonal properties,and the underwater data transmission can be realized by using the multiplexing technology based on the acoustic OAM.