Lam Bhan, Shi Dongyuan, Gan Woon-Seng, Elliott Stephen J, Nishimura Masaharu
School of Electrical and Electronic Engineering, Nanyang Technological University, Singapore, 639798, Singapore.
Institute of Sound and Vibration Research, University of Southampton, Southampton, SO17 1BJ, United Kingdom.
Sci Rep. 2020 Jul 9;10(1):10021. doi: 10.1038/s41598-020-66563-z.
Shutting the window is usually the last resort in mitigating environmental noise, at the expense of natural ventilation. We describe an active sound control system fitted onto the opening of the domestic window that attenuates the incident sound, achieving a global reduction in the room interior while maintaining natural ventilation. The incident sound is actively attenuated by an array of control modules (a small loudspeaker) distributed optimally across the aperture. A single reference microphone provides advance information for the controller to compute the anti-noise signal input to the loudspeakers in real-time. A numerical analysis revealed that the maximum active attenuation potential outperforms the perfect acoustic insulation provided by a fully shut single-glazed window in ideal conditions. To determine the real-world performance of such an active control system, an experimental system is realized in the aperture of a full-sized window installed on a mockup room. Up to 10-dB reduction in energy-averaged sound pressure level was achieved by the active control system in the presence of a recorded real-world broadband noise. However, attenuation in the low-frequency range and its maximum power output is limited by the size of the loudspeakers.
关闭窗户通常是减轻环境噪音的最后手段，代价是牺牲自然通风。我们描述了一种安装在家庭窗户开口处的有源声控系统，该系统可减弱入射声音，在保持自然通风的同时实现室内整体降噪。入射声音通过在整个孔径上最优分布的一系列控制模块（一个小型扬声器）被主动减弱。一个参考麦克风为控制器提供提前信息，以便实时计算输入到扬声器的抗噪声信号。数值分析表明，在理想条件下，最大有源衰减潜力优于完全关闭的单层玻璃窗所提供的完美隔音效果。为了确定这种有源控制系统在实际中的性能，在一个安装在模拟房间的全尺寸窗户的孔径中实现了一个实验系统。在存在录制的真实宽带噪声的情况下，有源控制系统实现了高达10分贝的能量平均声压级降低。然而，低频范围内的衰减及其最大功率输出受到扬声器尺寸的限制。
