预印件: 全球和本地优化光束形成用于宽带源
1German Aerospace Center (DLR), Department of Experimental Methods, Institute of Aerodynamics and Flow Technology, Göttingen, Germany.
The Journal of the Acoustical Society of America
|January 11, 2024
概括
本研究介绍了一种新的宽带能量功能,用于全球优化 (GO) 束形,改进声源识别和光谱重建. 新方法的性能优于标准GO和CLEAN-SC,特别是在复杂的声学场景中.
科学领域:
- 声学 声学 在声学上.
- 信号处理 信号处理
- 优化优化 优化优化
背景情况:
- 标准的全球优化 (GO) 波束成形由于频率依赖性质而面临宽带声源的挑战.
- 在标准的GO光束成形中,非线性能量函数可能导致局部最小值,使源的识别复杂化.
研究的目的:
- 为全球优化 (GO) 波束成形开发一种替代能源功能,专门用于声波宽带源.
- 为了提高准确性和简化源识别和光谱重建的过程.
主要方法:
- 使用跨光谱矩阵拟合方法,对频率的源属性进行参数化.
- 提出了一种新的宽带能源函数,该函数平均了点差函数 (PSF).
- 数字分析将拟议的方法与标准GO和CLEAN-SC (基于源连贯性的CLEAN) 进行比较.
主要成果:
- 拟议的宽带能源功能有效地平均了PSF,减轻了标准GO中发现的局部最小值的问题.
- 与标准GO和CLEAN-SC.相比,该方法在合成断上显示出更高的性能.
- 对于现实数据,拟议的方法和CLEAN-SC显示了相似的,优于标准GO的结果,对源假设违规的敏感性不同.
结论:
- 拟议的宽带能源功能为声源的GO光束形成提供了改进.
- 它简化了源标识和光谱重建,优于合成测试中的现有方法.
- 该方法显示出强度和潜力,用于识别复杂的声源,包括具有未知的特征的多极.
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