空间有源消声控制器的优化设计

Optimal Design of Controllers for Active Noise Cancellation in Three Dimensional Space

本文根据声源辐射理论和线性声场迭加原理,提出了一种三维空间有源消声的数值优化方法。通过最小化适当曲面上由初级声源和次级声源产生的合成声压的平方和,可以求得自由声场中给定区域或全空间声功率最小意义下次级声源的优化幅值和优化相位。这种方法可适用于单极子源和多极子源的情况。如考虑实际次级声源的特性,特别是其相位延迟特性,用本方法所求得的优化频响特性往往比有源消声中常用的“幅频平直、相位相反”的频响特性能更好地用实际模拟电路逼近,因此优化结果具有实用意义。实验表明,由本方法设计出的系统具有较好的消声效果。

This paper offers a numerical method for the optimal design of active noise cancellation(ANC)inthree dimensional space based on the theory of radiation of noise sources and the additivity of linear soundfield.By many lattice points on the proper camber,the optimal amplitude and phase at various frequenciesin the meaning of minimum sound power in a given region or in the whole space can be obtained.Themehtod is suitable for both mono-pole sources and multi-pole sources.Considering the characteristics ofpractical secondary noise sources,especially the phase shift,the optimal frequency response such designedcan be approached with analog circuit better than that obtained according to the principle of“straight am-plitude and anti-phase”,which has practical meaning to ANC.The experiments show that the optimal sys-tem can reduce the broad-band noise effectively.