Zhang Wen, Abhayapala Thushara D, Betlehem Terence, Fazi Filippo Maria
Center of Intelligent Acoustics and Immersive Communications, Northwestern Polytechnical University, 127 Youyi West Road, Xi'an, Shaanxi 710072, China.
Research School of Engineering, College of Engineering and Computer Science, The Australian National University, Canberra, Australian Capital Territory 0200, Australia.
J Acoust Soc Am. 2016 Sep;140(3):2134. doi: 10.1121/1.4963084.
Multi-zone sound control aims to reproduce multiple sound fields independently and simultaneously over different spatial regions within the same space. This paper investigates the multi-zone sound control problem formulated in the modal domain using the Lagrange cost function and provides a modal-domain analysis of the problem. The Lagrange cost function is formulated to represent a quadratic objective of reproducing a desired sound field within the bright zone and with constraints on sound energy in the dark zone and global region. A fundamental problem in multi-zone reproduction is interzone sound interference, where based on the geometry of the sound zones and the desired sound field within the bright zone the achievable reproduction performance is limited. The modal-domain Lagrangian solution demonstrates the intrinsic ill-posedness of the problem, based on which a parameter, the coefficient of realisability, is developed to evaluate the reproduction limitation. The proposed reproduction method is based on controlling the interference between sound zones and sound leakage outside the sound zones, resulting in a suitable compromise between good bright zone performance and satisfactory dark zone performance. The performance of the proposed design is demonstrated through numerical simulations of two-zone reproduction in free-field and in reverberant environments.
多区域声音控制旨在在同一空间内的不同空间区域独立且同时地再现多个声场。本文使用拉格朗日成本函数研究在模态域中提出的多区域声音控制问题，并对该问题进行模态域分析。拉格朗日成本函数的制定是为了表示在明亮区域内再现期望声场的二次目标，并对暗区和全局区域的声能进行约束。多区域再现中的一个基本问题是区域间的声音干扰，基于声音区域的几何形状和明亮区域内的期望声场，可实现的再现性能受到限制。模态域拉格朗日解证明了该问题的内在不适定性，在此基础上开发了一个参数——可实现性系数，以评估再现限制。所提出的再现方法基于控制声音区域之间的干扰和声音区域外的声音泄漏，从而在良好的明亮区域性能和令人满意的暗区性能之间达成适当的折衷。通过在自由场和混响环境中进行双区域再现的数值模拟，展示了所提出设计的性能。
