在动荡的大气中到达角度的波动
Vladimir E Ostashev1, Michael B Muhlestein1, D Keith Wilson1
1U.S. Army Engineer Research and Development Center, 72 Lyme Road, Hanover, New Hampshire 03755, USA.
The Journal of the Acoustical Society of America
|October 8, 2025
概括
大气动荡会扭曲声波到达角度 (AOA),影响传感器阵列性能. 这项研究量化了AOA波动变量,发现它随着流强度的增加而增加.
科学领域:
- 声学 声学 在声学方面
- 大气物理学 大气物理学
- 信号处理 信号处理
背景情况:
- 大气流导致声波的到达角 (AOA) 波动.
- 这些波动降低了用于源检测,定位和识别的传感器阵列的性能.
研究的目的:
- 从理论上分析通过两个麦克风测量AOA波动的方差.
- 以传播参数和流特征来表达AOA变异.
主要方法:
- 开发了AOA差异的理论模型.
- 利用·卡尔曼和科尔莫戈罗夫对大气动荡的光谱模型.
- 在典型大气条件下数值研究了AOA波动的标准偏差.
主要成果:
- AOA的差异取决于传播范围,麦克风分离,声频和流频谱.
- 使用科尔摩戈罗夫模型,变量简化为依赖于路径平均结构函数参数.
- AOA波动的标准偏差范围从几分之一度到1°-2°.
结论:
- AOA波动的标准偏差随着摩擦速度和表面热量流量而增加.
- 这些发现提供了关于大气边界层声音传播效应的见解.
- 这项研究对于在动荡环境中提高声学传感器阵列性能至关重要.
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