自适应有源声吸收中误差传声器的优化

针对一个基于最小均方算法的自适应有源消声控制系统，讨论了自由场空间有源声吸收中误差传声器位置的优化问题，分析了误差传声器位置对消声效果的影响，从理论上给出了一般的优化方法，并发现其误差传声器的最优位置并不是唯一的，同时系统初值的选择是实现最佳效果必须考虑的问题。

Optimization of Error Sensors Used in Adaptive Active Sound Absorption

In a previous paper, we obtained an optimization rule for error sensors by minimizing the acoustic power output of primary and secondary sources taken together. In some applications, acoustic power output of primary source remains unchanged and the effect on it of acoustic power output of secondary sources can be neglected. In such cases, we have active sound absorption. In this paper, we study the optimization of error sensors used in active sound absorption. We derived eq.(8) as the optimization rule for error sensors in active sound absorption. Our two research findings are: (1) From eq.(8), we may conclude that the number of error sensors should be equal to the number of secondary sources. Eq.(8) is also used to determine the position and amplitude of each of the error sensors. (2) From tests performed with an adaptive control system, we find that amplitude of error sensors can be optimized by adjusting the attenuation factor of the control system. But care must be exercised in the selection of the initial value of the attenuation factor (Fig.3b).