为研究声压传递函数的谐振频率对分布反馈式光纤激光水听器频响特性的影响,研制一种聚氨酯端面拉伸式增敏结构的光纤激光水听器。基于电声类比理论建立了声压传递函数模型,仿真分析水听器各结构、材料参数与水听器声压传递函数的关系,制作水听器原型样品并进行了实验研究。实验测得,该结构水听器在10~2000 Hz 频率范围内的平均声压灵敏度为-142.8 dB,波动幅度小于±1.5 dB,且谐振频率出现在3150 Hz附近,与仿真分析结果吻合较好,表明光纤激光水听器的声压灵敏度频响特性可有效预测以及精细优化,这对于应用于小型水下作战平台的小尺寸阵元的研制具有重要指导意义。

To study the influence of the resonant frequency in sound pressure transfer function on the frequency response characteristics of distributed feedback fiber laser hydrophone, a sensitivity enhanced structure through polyurethane end surface pulling is designed. The sound pressure transfer function model is established based on electro-acoustic theory. Then the relationship between the structure and material parameters with the sound pressure transfer function is simulated, and prototypes of hydrophones are fabricated and tested. The results show that the average sound pressure sensitivity reaches to -142.8 dB with the fluctuation less than ±1.5 dB in the frequency range of 10~2000 Hz and the resonant peak appears near 3150 Hz, which agrees well with the simulation result. The frequency response characteristics of fiber laser hydrophone can be effectively predicted,refined and optimized, which is of great guiding significance for the development of small array elements used in small-sized underwater combat platform.