微机械阵列滤波传声器的动态特性

Dynamic Characteristic of Micromachined Arrayed Microphone

对近年来硅微机械加工技术 (MEMS)工艺研制的几种微传声器进行了论述 ,对其优缺点进行分析和研究表明 :这些传统的传声器主要起声电转换的作用 ,对噪声信号的滤波处理是由专用滤波电路完成 ,或者用数字滤波进行处理。为此提出了一种硅微阵列滤波器传声器 ,在转换信号的同时实现滤波。讨论了阻尼和硅簧片根数对动态特性的影响 ,并由此得出 :阻尼的增加会降低传声器的灵敏度 ,簧片根数的增加可以改善灵敏度曲线。而且在获取噪声信号的同时能够实现滤波。

Several kinds of microphone developed via silicon Micro Electro Mechanical System (MEMS) processes in recent years are investigated in this paper. The analysis and research of the merits and demerits of them show that: these conventional microphones mainly function as acoustic electric converters; the filtering against noise is implemented by a special filter circuit or a digital filter. Therefore, a design method for silicon micro array filter microphone is presented, where the filtering is achieved while converting signals. The effects of damping, silicon reed number and sensor element pair on dynamic characteristic are discussed; it follows that: Increasing damping can reduce microphone's sensitivity, while increasing silicon reed number can improve the sensitivity curve, furthermore, the implementation of the filter function is simultaneous with acquiring of the noise signal.