水声工程中基于均匀圆阵列的涡旋声波性能分析*

声波作为信息和能量的载体，一直以来在水下通信中被广泛采用，但尚未解决带宽窄、速率低的问题。在光学领域和电磁波领域，轨道角动量都表征了螺旋相位结构的自然属性；通过引入轨道角动量到声学领域中，水声通信系统的传输能力以及频谱效率都得到扩展。基于换能器圆阵列产生涡旋声波进行分析和检测，研究涡旋声波波束的阵列产生方法，给出涡旋声波波束在水下传播的特性。在主轴方向，采用均匀圆阵列产生不同拓扑模式的涡旋声波波束，确定轨道角动量拓扑模式与换能器阵列之间的对应关系；为生成不同拓扑模式下的涡旋声波，研究阵列单元数目、阵列半径、传输频率等对涡旋声波的影响。通过研究发现模式数越高，涡旋声波主瓣波束角越大，主瓣峰值越小。阵列半径越大，主瓣波束角越大，而主瓣峰值则随着阵列半径的增大而减小；频率越高，主瓣波束角越小，主瓣峰值变化不大；阵列单元数对主瓣波束角无影响，但与主瓣峰值成正比关系，阵列单元数越多，主瓣峰值越大。

Performance analysis of vortex acoustic wave based on uniform circular array in underwater acoustic engineering

As a carrier for information and energy, acoustic waves have been applied in underwater communication widely, however the narrow band and low transmission speed are the main problems. Whether in the field of optics or electromagnetic waves, the orbital angular momentum (OAM) represents the natural properties of the spiral phase structure. By introducing the OAM into the acoustics field, the transmission capacity and spectrum efficiency of the underwater acoustic communication system can be expanded. Based on the analysis and detection of the vortex acoustic wave generated by the circular array of transducers, we studied the array generation method of the spiral acoustic beam, and gave the characteristics of the vortex acoustic beam when propagating under the water. In the direction of the main axis, the uniform circular array was used to generate different topological acoustic vortex. To determine the relationship between the OAM topology mode and the transducer array, the spiral acoustic waves in different topology modes were generated, and the number of array elements, array radius, transmission frequency, etc. were investigated to give the effects on OAM acoustic vortex.