主动降噪技术在航空外场中的应用

为了降低航空外场的环境噪声，提出了一种将主动降噪技术运用在航空外场中的方案. 用音频和声学分析仪对航空外场发动机的噪声进行采集，得出航空外场噪声的频谱图；通过主动降噪芯片AS3502以及相关的硬件电路对频谱图中频率范围为800Hz以下的低频噪声进行降噪处理，得到处理后的音频信号，并通过Matlab仿真显示；将仿真结果与经过物理隔音处理后的噪音信号进行对比和分析. 结果表明主动降噪技术在低频范围内可将总体信噪比提高6dB，有效地降低航空外场的噪声.

Application of active noise reduction technology in field of aircraft

To reduce the ambient noise outside the field of aviation, applying a active noise reduction technology in the field of aviation was proposed. We used the audio and acoustic analyzer to collect the engine noise of aviation field and got the spectrogram. We deposed the low frequency noise below 800　Hz by active noise reduction chip AS3502 and hardware circuit, and obtained the audio signals which were simulated by Matlab, Compared the simulated results with the noise signals by the physical insulation, the results show that the active noise reduction technology improves signal-to-noise ratio of the low frequency by 6　dB, effectively reducing the noise outside the field of aviation.