新型曲面换能器阵指向性研究

利用抛物面几何结构的自聚焦性能优化设计了一种新型的抛物面换能器阵。基于声场理论,推导出换能器阵的三维指向性函数表达式。数值仿真了阵元数目、抛物面焦距和工作频率等参数对阵列指向性因数的影响。仿真实验结果表明,相对于传统平面圆环阵列而言,在换能器目数相同的情况下,抛物面相控阵列指向性因数增加了1倍,具有较高的指向性和抑制旁瓣能力,是较理想的组合声源。通过优化参数,抛物面换能器阵可获得最佳指向性,进而为声频定向扬声器的设计及研究提供了理论基础。

Research on the Directivity of a New Curved surface Transducer Array

A new type of paraboloidal transducer array was presented on the base of curved autofocus with paraboloidal geometry. According to sound field theory, the three dimension directivity formula was calculated. Several factors such as element number, focus and frequency that affected the directivity function were numerical simulated. The results showed that the directivity function of paraboloidal transducer doubled compared to conventional planar circular array with same number of transducers. This curved surface array had an intensive directivity and ability of suppressing side slobs. An optimum distribution of sound field could be obtained by optimizing the array parameters, which provided a theoretical foundation for the design and research of audio directional loudspeaker.