车内有源噪声控制的研究

用传递函数法建立了模拟汽车车厢内声学特征的主动噪声控制理论模型。开发完成了封闭空间主动噪声控制试验系统的硬件和软件。用几种纯音信号对模拟车厢进行了空间主动降噪试验。结果表明，对于１３９Ｈｚ的纯音噪声信号，在封闭空间内取一个测量面，其上的噪声平均降低了１０ｄＢ，而对于１５０Ｈｚ的纯音噪声信号则平均降低了５ｄＢ，高于２００Ｈｚ的几个纯音噪声信号则可以得到较好的区域降噪。证实了车内有源噪声控制的可行性。

Study on active noise control inside automobile cabin

The acoustical behavior of an automobile cabin was analyzed. The theoretical model of the active noise control system was built by use of transfer function method. On this basis, an active noise control system was designed, then its hardware and software were developed and tested to control stable pure noise in this enclosure. The test was repeatedly carried with pure noises at variant frequencies. The results of the test show that the meaning reduction over the measured plane is about 10 dB for the noise at 139 Hz and 5 dB at 150 Hz. The noise with frequencies over 200 Hz was attenuated as well in some certain regions. At last, the rule of the monitoring microphone distribution was discussed to gain a good control result.