无次级通道建模有源噪声控制算法的实验研究

以管道中有源噪声控制为实验平台,基于ADSP21161N数字信号处理评估板实现了本文作者早先提出的不需要次级通道建模的基于LMS方法的四方向搜索型有源控制算法,并给出了该算法在实际应用中收敛系数的选取原则。针对单频和多频噪声的实验结果表明,前人两方向搜索型有源控制算法在大部分频率上都能收敛,但在次级通道相位为±90°的频率不能收敛,而本文作者所提出的四方向变收敛系数搜索型算法,在所有频率都能快速收敛。

Experimental study of the active noise control algorithms without secondary path modeling

Based on the experimental setup of Active Noise Control(ANC) system in a duct,the Quad Direction Search Least Mean Square(QDSLMS) algorithm,proposed in a 2008 paper by some of the present authors,which does not need secondary path modeling,is implemented on an ADSP 21161N evaluation DSP board.The principle of step size selection is analyzed and suggested for practical applications.The experimental results with the sinusoidal noise show that the ANC algorithm based on the original two direction search method(DSLMS) works well at most frequencies,but failed at the frequencies where the phase of the secondary path transfer function is 90 or-90 degrees;on the other hand,our proposed QDSLMS algorithm works well at all frequencies.