摘要： 多波束渔用声呐是利用水声学方法探测海洋鱼类资源数量和空间分布信息的主要工具。本文阐述了多波束渔用声呐原理及工作过程，采用水声学理论分析的方法并结合多波束渔用声呐在海洋渔业捕捞中的使用场景，给出了作用距离预报模型，分析了影响探测性能的主要因素；针对远洋围网和拖网捕捞的全方位探测需要，重点仿真分析了圆柱阵多波束渔用声呐最优工作频点选取方法及探测性能，揭示了最大探测距离、换能器基阵最小尺寸及最优工作频点3者之间的相互制约机制，分别对噪声和混响影响条件下的探测性能进行评估，给出了在换能器基阵尺寸给定条件下实现最大探测距离的最优工作频点，及在最大探测距离设定条件下实现最小换能器基阵尺寸的最优工作频点; 提出了多波束渔用声呐在部署条件或使用场景确定下的最优化频点选取方法，并评估了不同情况下的渔用声呐探测性能，具体明确了适用于远洋捕捞场景中的换能器直径在0.375 m，针对0 dB目标鱼群的最大探测距离为2 600 m，最优工作频点应选取为25 kHz，本研究为后续自主进行装备研制、测试和试验提供了理论指导。

关键词: 多波束渔用声呐, 探测性能, 最优工作频点, 换能器基阵

Abstract: Multi-beam fishery sonar is an important tool for marine fish resources detection and spatial distribution analysis applying . hydroacoustic methods. This paper expounded the principle and working process of multi-beam fishery sonars. By analyzing underwater acoustics theories integrating with the application of multi-beam fishery sonars in marine fishing, this paper offered a range prediction model, and analyzed the main factors affecting the detection performance. Aiming at the omnidirectional detection of high sea purse seine and trawl fishing, this paper focused on the simulation and analysis of selection methods for the optimal operating frequency, and detection performance for cylindrical array multi-beam fishery sonars, revealing the constraint relationship among the maximum operating range, minimum size of transducer array and the best working frequency. The detection performance under the influence of noise and reverberation was evaluated respectively, the optimal operating frequency point to achieve the maximum detection distance under the given size of the transducer array and the optimal operating frequency point to achieve the minimum size of the transducer array under the setting of the maximum detection distance were both given. An optimal frequency selection method for multi-beam fishery sonars under certain deployment or application conditions was proposed, and the detection performance of fishery sonar was evaluated. It was proved that the diameter of the transducer applicable to the ocean fishing was 0.375 m, the maximum detection distance for the 0dB shoal was 2 600 m, and the optimal operating frequency best be 25kHz. The results will provide theoretical guidance for follow-up equipment development, testing and experimentation.

Key words: multi-beam fishery sonar, detection performance, optimal working frequency, size of transducer array