调控明区声场重建性能和暗区声能量的综合控制方法

A control method for balancing the reproductive performance and the acoustic contrast performance in a personal audio system

采用扬声器阵列的空间局部声场重建是指控制扬声器阵列输入的幅值和相位,使得目标声场聚焦于特定区域（明区）内,同时降低其他区域（暗区）的声能量。为满足车内乘客对独立视听环境需求的不断提高,研究车内局部声场重建。考虑到扬声器有驱动功率限制和传递函数存在测量误差,提出一种调控明区声场重建性能与暗区声能量平衡的鲁棒性控制方法（PSR-RC,Personal Sound Reproduction with Robust Control）,采用路径跟踪法获得不同频率下的最佳权重因子。仿真结果与实车测试性能显示,PSR-RC算法保证明区重建声场性能的基础上,通过最小化暗区能量,获得了较好的明暗区声能量对比度。仿真与实车试验结果保持了较好的一致性,控制点区域的控制效果与非控制点区域的控制效果也保持了较好的一致性,验证了PSR-RC算法的正确性和可靠性。

Achieving a personal audio system using a loudspeaker array means that generating a clearly desired audible sound in one listening zone, called bright zone, whilst ensuring that it is inaudible in other zones, called dark zones. The car cabin is becoming an interesting environment for a personal audio system. In order to achieve a personal audio system inside a car cabin, with the array effort of the loudspeaker array constrained and the measured errors of transfer functions existing in the practical application, PSR-RC method is proposed to balance the reproductive performance of the bright zone and the sound energy in the dark zones. Path-following algorithm is applied for the identification of optimal weights at different frequencies. From the results of the off-line simulation and the real-time experiment, it can be concluded that with the speech quality of the reproductive sound in the bright zone guaranteed, PSR-RC method can achieve a satisfied contrast performance between the bright zone and dark zones. The simulation results match the results of the real-time experiment well and the performance of the non-controlled points also matches the performance of the controlled points, which shows the accuracy and validity of PSR-RC method.