海洋波导中的噪声共变矩阵的固有值
Jie Li1, Peter Gerstoft2, Jun Fan1
1Collaborative Innovation Center for Advanced Ship and Deep-Sea Exploration, State Key Laboratory of Ocean Engineering, Shanghai Jiao Tong University, Shanghai 200240, China.
The Journal of the Acoustical Society of America
|July 8, 2024
概括
对垂直和水平线阵列的声噪声共变矩阵 (CM) 的研究揭示了不同的固有值光谱. 这些光谱提供了对水下环境和噪声源的洞察,有助于声波阵列处理.
科学领域:
- 海洋声学 海洋声学
- 信号处理 信号处理
- 地质物理学 地质物理学
背景情况:
- 噪声共变矩阵 (CM) 的自身值 (EV) 光谱是水下声环境的特征.
- 了解噪音源对于有效的声波阵列处理至关重要.
研究的目的:
- 在深水和浅水中对垂直线阵列 (VLA) 和水平线阵列 (HLA) 的EV光谱进行数值研究.
- 实证地将这些光谱与光束形成输出宽度联系起来.
- 分析环境因素对不同水深的噪音CM的影响.
主要方法:
- 对VLA和HLA在深水和浅水中噪声CM的数值模拟.
- 从理论和观测样本CM.CM.中获得的EV光谱的分析.
- 实验数据与波导和同源噪声模型的比较.
主要成果:
- 在深水中,HLAs表现出与EV频谱相似的等离子噪声CM,而VLAs表现出与海面和底部反射噪声相关的两步EV跳跃的非等离子CM.
- 在浅水中,VLA噪声CM是复杂的,受到环境参数和阵列深度的影响.
- 实验VLA噪声数据与波导噪声模型比3D同位素模型更好地对齐.
结论:
- 噪声CM的自身值光谱提供了关于水下声环境和噪声来源的有价值信息.
- 阵列几何和水深显著影响噪声CM特征.
- 波导噪声模型在某些水下场景中提供了更准确的VLA噪声表示.
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