Rafaely Boaz
Department of Electrical and Computer Engineering, Ben-Gurion University of the Negev, Beer-Sheva 84105, Israel.
J Acoust Soc Am. 2009 May;125(5):3006-17. doi: 10.1121/1.3110131.
Active control of sound has been employed to reduce noise levels around listeners' head using destructive interference from noise-canceling sound sources. Recently, spherical loudspeaker arrays have been studied as multiple-channel sound sources, capable of generating sound fields with high complexity. In this paper, the potential use of a spherical loudspeaker array for local active control of sound is investigated. A theoretical analysis of the primary and secondary sound fields around a spherical sound source reveals that the natural quiet zones for the spherical source have a shell-shape. Using numerical optimization, quiet zones with other shapes are designed, showing potential for quiet zones with extents that are significantly larger than the well-known limit of a tenth of a wavelength for monopole sources. The paper presents several simulation examples showing quiet zones in various configurations.
利用来自噪声消除声源的相消干涉，已采用有源声控制来降低听众头部周围的噪声水平。最近，球形扬声器阵列作为多通道声源受到了研究，它能够产生具有高度复杂性的声场。本文研究了球形扬声器阵列在局部有源声控制中的潜在应用。对球形声源周围的初级和次级声场进行理论分析表明，球形声源的自然安静区呈壳状。通过数值优化，设计了其他形状的安静区，显示出安静区范围可能显著大于单极子声源十分之一波长这一众所周知的限制。本文给出了几个模拟示例，展示了各种配置下的安静区。
