微型声频定向换能器阵列指向性研究  

Research on the Directivity of Micro Audio Directional Transducer Array

作　　者：李学生[1] 徐利梅[1] 陈敏[1] 许亮峰 缪建民[3] 

机构地区：[1]电子科技大学空天科学技术研究院,四川成都611731 [2]诺基亚中国研究中心,北京100176 [3]南洋理工大学MEMS中心

出　　处：《压电与声光》2012年第4期553-556,560,共5页Piezoelectrics & Acoustooptics

基　　金：国家自然科学基金资助项目(60901062)

摘　　要：通过对微型声频定向换能器阵列的指向性参量研究,设计并制造了基于微机电系统(MEMS)的锆钛酸铅(PZT)薄膜换能器阵列,为声频定向扬声器的发声部件微型化提供了一种可行的实现方法。从理论上分析了阵元半径、阵元个数和阵元中心间距等结构参数对指向性的影响,确定各阵元正方形排列可获得预期的圆柱形声音传播空间,阵元数量越多,声波指向性越强,并指出当阵元间距约为波长的1/2时,旁瓣抑制效果最明显。最后对微型MEMS换能器阵列实物做指向性测试,实验结果与理论分析结果基本一致。A MEMS-based PZT film transducer array has been designed and fabricated to verify the feasibility of miniaturization of the emitter in the audio directional loudspeaker through researching the parameters of the directivity of micro audio directional transducer array in this work. The effects of the radius, quantities and space of the array elements on the directivity have been analyzed theoretically. The results indicate that the elements should be arranged in a square to realize the expected cylindrical sound beam and more elements can result in better performance of directivity. When the spacing between two elements are approximate to a half of wavelength, the amplitude of the side lobes are suppressed most effectively. In the end,the directivity characteristic of the MEMS-based micro array has been tested and the experimental results are good with the theoretical results.

关 键 词：声频定向扬声器 微机电系统(MEMS) 锆钛酸铅(PZT)薄膜 换能器阵列 指向性 

分 类 号：TN64[电子电信—电路与系统]