关键词: 弱反射光纤光栅水听器, 分布式, 波束形成, 声压灵敏度, 单元指向性

Abstract: A compliant distributed weak reflection fiber Bragg grating hydrophone linear array with continuous spiral winding and sensitization was devised to improve the target detection performance of fiber optic hydrophone line array. Based on the theory of elasticity, a hydrophone acoustic pressure phase sensitivity model was developed by continuously and spirally winding fiber around a hollow cylinder made of high density polyethylene. If the fiber between gratings was 10 m long, the sensitivity of the hydrophone element was -133.99dB (re 1 rad/μPa). An anechoic water tank experiment facility was constructed for a six-element distributed weak reflection fiber Bragg grating linear hydrophone array. The experimental results revealed that the average acoustic pressure sensitivity of hydrophone was −136.00 dB. The overall tendency of the element directivity test curve was consistent with that of the theoretical curve. The test and theoretical curves of beam response basically coincided in terms of azimuth and beam width for the maximums.

Key words: weak reflection fiber Bragg grating hydrophone, distributed, beam formation, acoustic pressure sensitivity, element directivity