Berkhoff Arthur P
University of Twente, Faculty of Engineering Technology, Applied Mechanics and Data Analysis, Drienerlolaan 5, 7522NG Enschede, The Netherlands.
J Acoust Soc Am. 2021 Jan;149(1):645. doi: 10.1121/10.0003376.
This paper presents a solution method for a fixed multichannel frequency domain feedforward controller, which is optimized for different sound field disturbances, each corresponding to a different control objective. A controller determined on the basis of identical control objectives for different disturbances can be solved efficiently by using the inverse of two relatively small matrices, the Hermitian square of the secondary path and the cross-spectral density matrix of all combinations between the reference signals. In contrast, the dependence between the disturbance and the control objective results in a large matrix, which may not fit in the memory of a computer. To design the controller for systems with relatively large numbers of sensors and sources, an iterative method based on the conjugate gradient technique is used. A preconditioner based on a disturbance-independent control objective is proposed. This preconditioner improves the convergence rate for some applications. A numerical example of the iterative method is given for active control of the acoustic field inside a room in which a disturbance dependent weighting function is applied to the cost function. It is shown that the iterative method efficiently finds the solution for the disturbance dependent active noise control problem.
本文提出了一种针对固定多通道频域前馈控制器的求解方法，该控制器针对不同的声场干扰进行了优化，每种干扰对应不同的控制目标。对于不同干扰基于相同控制目标确定的控制器，可以通过使用两个相对较小矩阵的逆来有效求解，这两个矩阵分别是次级路径的埃尔米特平方以及参考信号之间所有组合的互谱密度矩阵。相比之下，干扰与控制目标之间的相关性会导致一个大矩阵，可能无法装入计算机内存。为了为具有相对大量传感器和源的系统设计控制器，使用了一种基于共轭梯度技术的迭代方法。提出了一种基于与干扰无关的控制目标的预处理器。该预处理器提高了某些应用的收敛速度。给出了该迭代方法的一个数值示例，用于室内声场的有源控制，其中将与干扰相关的加权函数应用于代价函数。结果表明，该迭代方法能够有效地找到与干扰相关的有源噪声控制问题的解。
