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一个波面适应式传感波束造型器用于海洋声波导
Anil Ganti1, Michael Martinez1, Granger Hickman1
1Electrical and Computer Engineering, Duke University, Durham, North Carolina 27704, USA.
The Journal of the Acoustical Society of America
|October 18, 2023
概括
这项研究介绍了一种用于被动声纳的新型波面适应感应 (WAS) 波束变频器. 在浅水中,WAS光束转换器有效地将目标与干扰分开,性能优于传统方法.
科学领域:
- 声学 声学 在声学方面
- 信号处理 信号处理
- 海洋工程 海洋工程
背景情况:
- 传统的波束成形在被动声纳中普遍存在,但在复杂的多路径环境中,它与信号不匹配作斗争.
- 现有的强大的自适应光束成形方法往往会降低适应性,并且由于增加的约束因素,无法充分抑制干扰.
- 信号子空间建模中的不确定性限制了在动态的水下环境中传统的自适应光束造型器的有效性.
研究的目的:
- 为在不确定的浅水环境中运行的被动声纳系统开发一款强大的自适应式光束变换器.
- 通过避免传统建模约束来增强目标与强干扰的分离.
- 为了在复杂的声学条件下提高被动声纳的性能.
主要方法:
- 使用盲源分离技术,以适应性地估计目标和干扰的空间波线.
- 利用时间光谱的差异和目标和干扰之间的频率选择性多路径色.
- 在不施加方向增益约束的情况下构建无信号共变矩阵,从而导致波面自适应传感 (WAS) 波束造型器.
主要成果:
- 波面自适应传感 (WAS) 波束制造器成功地将目标从强干扰中分离出来,即使干扰处于目标的常规光束宽度内.
- 模拟结果在现实的浅水道中显示出卓越的性能.
- 使用SWellEx96 S59数据与注入目标的验证证实了WAS光束变器的有效性.
结论:
- 拟议的波面自适应传感 (WAS) 波束变频器为被动声纳在具有挑战性的浅水环境中提供了重大进步.
- 通过利用盲源分离,WAS克服了传统和现有的强大的自适应光束造型器的局限性.
- 这种方法提供了增强的目标检测和干扰抑制能力,这对于水下声学应用至关重要.
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