扬声器相控阵列三维声场指向性研究

Discussion on Directivity of Three-Dimensional Sound Field of Loudspeaker Phased Array

摘要: 传统有源噪声控制采用的控制声源为无指向性的普通扬声器，但是在实际应用中，噪声往往是斜入射的，最有效的控制方法是根据噪声的入射方向进行噪声控制，这就需要一个具有指向性的声源。针对这一问题，设计开发了扬声器相控阵列，并对其三维声场的指向性进行研究。研究相控阵的指向性函数和偏转理论，利用相同的扬声器设计了14元线型阵列和4 × 4的平面阵列，分别在露天半自由场和半消声室中对阵列声场进行大量实验测试，实现了阵列的指向性偏转并与仿真结果进行对比。结果表明：扬声器相控阵列在低频频率下具有精准可控的强指向性，可作为空间有向大功率声源使用。

Abstract: Traditional active noise control uses a control source of non-directional ordinary loudspeakers, but in practice, noise is often incident obliquely, and the most effective control method is noise control according to the direction of incidence of noise, which requires a source with directivity to address this problem; a loudspeaker phased array is designed and developed, and the directivity of its three-dimensional sound field is investigated. The directivity function and deflection theory of the phased array are investigated. A 14-element linear array and a 4×4-planar array are designed using the same loudspeakers, and the array sound field is tested in extensive experiments in an open-air semi-free field and a semi-anechoic chamber, respectively, to achieve the directivity deflection of the array and to compare it with the simulation results. The results show that the loud-speaker phased arrays have precise and controllable strong directivity at low frequencies and can be used as a spatially directed high power source.