海豚超声接收的指向性机理研究

经过长期自然演化，海豚进化出高效的水下超声生物声纳。海豚声接收系统是实现其生物声纳功能至关重要的环节。现有研究尚未阐明海豚声接收过程中复杂的声场分布以及头部声接收系统的有关声学结构在接收声场中的作用。本项目围绕海豚超声接收的指向性机理开展研究。首先应用计算机断层扫描成像技术重建海豚头部声接收系统的三维结构，并利用超声测量方法实验测量海豚软组织的声学参数，从而获得海豚声接收系统的复杂声学结构。此外，根据实验测量，建立海豚声接收系统的有限元声场计算模型，研究超声接收的多通道声传输特性，阐明指向性超声接收机制，并揭示各声学结构对接收声场的调控作用。进一步，实验测量海豚超声接收的指向特性和多通道声传输特性，并与有限元模拟结果相比较，改进海豚声接收模型。本项目为海豚声接收研究提供新思路，对于阐明海豚超声接收的指向性机理有重要科学意义，对于发展基于仿生学的声接收技术有潜在应用价值。

After a long period of natural evolution, dolphin has evolved an efficient underwater ultrasound biosonar. Dolphin sound reception system plays an important role in the realization of biosonar function. Previous studies have not yet found out the complex acoustic field distribution and the role of the acoustic structures in the dolphin ultrasound reception system. This project focuses on the directional mechanism of dolphin ultrasound reception. We first apply computerized tomography technology to reconstruct the head of dolphin and measure the acoustic parameters of different soft tissues by ultrasonic experiment. The complex three-dimensional structure of dolphin reception system is then reconstructed. In addition, a finite element model of dolphin ultrasound reception is established to investigate the multiple-path transmission characteristic and directional reception mechanism. The regulation effect of soft tissues on receiving acoustic field is revealed. Furthermore, the experimental measurements of directional and multiple-path transmission characteristics of dolphin ultrasound reception are performed and compared with the simulated results of finite element simulations. This study provides new ideas for investigating dolphin ultrasound reception, has important scientific significance for understanding the directional reception mechanism, and has potential application for developing bioinspired underwater acoustic reception devices.