从动态粗的海面使用有限差异时间域方法进行水下声学传播和散射
Alex Higgins1, Martin Siderius1
1Electrical and Computer Engineering, Portland State University, Portland, Oregon 97201, USA.
The Journal of the Acoustical Society of America
|July 3, 2024
概括
下一代SONAR需要模拟动态的海面. 这项研究使用有限差异时间域方法来模拟海面的粗和运动,改进了声学传播模型.
科学领域:
- 海洋声学 海洋声学
- 计算物理学的计算物理.
- 信号处理 信号处理
背景情况:
- 传统的水下声学传播模型假定海面是静态的.
- 下一代SONAR利用长时间的传输,与动态的海面相互作用.
- 这种相互作用导致传输损失和多普勒效应,挑战目前的模型.
研究的目的:
- 开发和实施一个全面的波浪传播模型,考虑海面的粗和运动.
- 为了研究随时间变化的海面对水下声学信号的影响.
- 为了提高声波传播模拟用于SONAR应用程序的准确性.
主要方法:
- 实施了有限差异时间域 (FDTD) 方法来建模海面动态.
- 开发了可变子网海面边界技术,以提高FDTD准确性.
- 利用皮尔森-莫斯科维茨光谱来表示基于风状况的粗,随时间变化的海面.
主要成果:
- FDTD模型成功模拟了海面粗和运动对声学传播的影响.
- 开发的子网技术提高了模拟的准确性.
- 该模型提供了对动态海面造成的传输损失和多普勒位移的洞察.
结论:
- 全波传播模型对于理解动态海面的声学现象至关重要.
- 具有时间演变的边界条件的FDTD方法为准确的模拟提供了一种可行的方法.
- 这项研究有助于设计更好的SONAR系统,因为它考虑了复杂的海面相互作用.
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