浅海内波环境下声场干涉条纹的稀疏重建

Sparse reconstruction of acoustic interference fringes in shallow water and internal wave environment

针对浅海内波引起的干涉条纹“扭曲”问题,利用耦合模理论,提出了一种声场干涉条纹的稀疏重建方法.该方法主要分为两个步骤:(1)将干涉条纹近似为几组二维正弦的和,并用向量有限新息率方法重建;(2)根据耦合模理论,未耦合模对的二维频率不随内波位置变化,而耦合模对的频率随内波位置变化.因此,二维频率可以分为两部分:未耦合模对包含了波导的信息,可用于背景环境规则干涉条纹的重建和波导不变量的估计;耦合模对包含了内波的位置信息,可用于内波的追踪.仿真结果表明,本文方法在内波环境下能够提供有效的干涉条纹重建、波导不变量估计和内波的追踪.

To reduce the distortion of acoustic interference fringes caused by internal waves in shallow water,a sparse reconstruction method of acoustic interference fringes is proposed in this paper according to the coupled mode theory.The proposed method consists of two steps:(1)The interference fringes are approximated to the sum of several two-dimension sinusoids,which are sparsely reconstructed by the vector finite rate of innovation method.(2)According to coupled mode theory,two-dimension frequencies related to uncoupled mode pairs do not vary with the location of internal waves.However,two-dimension frequencies related to coupled mode pairs vary with the location of internal waves.So these frequencies are classified into two parts.The uncoupled mode pairs are used to recover the regular interference fringes and estimate the waveguide invariant in the background environment.The coupled mode pairs are used to track the locations of internal waves.The simulation results show that the proposed method can effectively provide interference fringe reconstruction,waveguide invariant estimation,and internal wave tracking in the internal wave environment.