论文标题：Active control of broadband sound through the open aperture of a full-sized domestic window

期刊：Scientific Reports

作者：Bhan Lam, Dongyuan Shi et.al

发表时间：2020/07/09

数字识别码：10.1038/s41598-020-66563-z

微信链接：点击此处阅读微信文章

《科学报告》发表的一项原理验证研究Active control of broadband sound through the open aperture of a full-sized domestic window介绍了一种新型降噪设备，它可以将通过打开的窗户传进来的声音降下来。该设备适合双扇滑动窗，能够将城市交通噪声的可感知响度最高降低一半（降低10分贝）。

新加坡南洋理工大学的Bhan Lam及同事组装的这种设备包括24个扬声器（直径分别为4.5 cm），扬声器呈网格形式固定在窗户内侧的格栅上，窗户外侧有一个传感器。如果传感器检测到建筑物外部的噪声，扬声器便会发出和该噪声频率相同的“反噪声”（anti-noise），但是声波相反。因此，“反噪声”和被检测到的噪声相互抵消，从而降低进入室内的噪声污染——甚至在窗户打开的情况下也可以。

图a: 模拟室，图b：在模拟室内工作的自动噪声控制设备 | credit: Lam et al.

在测试中，作者将该设备置于一间模拟室的窗户上，并在两米之外通过一个扬声器播放公路交通、火车和飞机的噪声。室内的18个麦克风检测到了噪声控制设备启动前后的噪声变化。作者发现频率高于300Hz的声音（如公路交通和火车噪声）最高下降了10分贝。

以上发现表明这种设备成功地降低了通过打开的窗户传输的噪声大小。作者希望可以利用该设备，在窗户打开的情况下，一边降低传入室内的噪声水平，一边保持室内通风，从而帮助改善城市居民的健康。

摘要：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.

（来源：科学网）