【摘要】 基于实时数字信号处理系统理论 ,讨论有源噪声控制系统的电子设计方法。通过对控制时序的分析 ,设计了一实时多通道自适应控制系统 ,该系统以 PC为主控机 ,以 DSP TMS32 0 - C30为从处理机 ,具有多路传感器同时输入和扬声器同时输出通道。该系统被应用于国产某型螺桨飞机的舱内噪声控制 ,取得了满意的降噪效果更多还原

【Abstract】 Active noise control, as applied to engineering projects, began around 1990. We designed a multi channel active noise control (ANC) system for reducing the noise in front cabin in Chinese Y 7 propeller driven aircraft. In ANC applications, in order to reduce effectively the noise level in a large space, we have to match at any time the generated secondary sound field with the original primary sound field, so that a percentage of the entire primary noise field is effectively cancelled out by the entire secondary noise field. Via analyzing ANC time sequences, we developed a multi channel adaptive control system that can simultaneously detect multiple error inputs and produce multiple canceling outputs. Our system consists of PC as main controller, TMS320-C30 DSP chip as slave processor, 16 A/D input channels and 8 D/A output channels. Applying our system to Chinese Y 7 aircraft appears to be successful; test results show that noise level of Y 7′s blade pass frequency (BPF) and its secondary harmonic frequency (2BPF) are attenuated by 13.4 dB and 5.5 dB respectively. Work remains to be done before our system becomes a part of Y 7 aircraft in actual flights.更多还原