MEMS矢量传声器低噪声优化设计  

Low Noise Optimization Design of MEMS Vector Microphone

作　　者：周瑜[1] 李光[1] 涂其捷 李晓光[1] 谢奕 刘云飞[1] ZHOU Yu;LI Guang;TU Qijie;LI Xiaoguang;XIE Yi;LIU Yunfei(The Third Research Institute of China Electronic Technology Group Coirporation,Beijing 100015,China)

机构地区：[1]中国电子科技集团公司第三研究所,北京100015

出　　处：《电声技术》2018年第4期4-8,共5页Audio Engineering

摘　　要：MEMS矢量传声器是目前已知的唯一一种可以直接精确测量声场质点振速的声学传感器,在噪声振动测量、材料特性分析以及国防领域有着广泛的应用前景。矢量传声器的自噪声水平直接影响了目标声源的有效探测距离和定向精度,是MEMS矢量传声器研制与应用的关键。本文在研究MEMS矢量传声器工作机理的基础上,分析得出敏感结构的电源模块自噪声是影响MEMS矢量传声器自噪声水平的主要因素之一。因此,本文设计制作了基于LT3045-1的低噪声电源模块,经测试其自噪声水平已接近铅酸电池。随后,将该电源模块应用于MEMS矢量传声器,有效改善了矢量传声器的自噪声性能,测得传声器自噪声水平接近于国外同类型MEMS矢量传声器产品,实现了国产低噪声矢量传声器优化制作。MEMS vector microphone is the only known acoustic sensor,which can directly and accurately measures the vibration velocity of sound field. They have broad application prospects in noise and vibration measurement,material property analysis,and defense. The self-noise level of the vector microphone directly affects the effective detection distance and orientation accuracy of the target sound source,which is the key to the development and application of the MEMS vector microphone. Based on the study of the working mechanism of MEMS vector microphone,this paper analyzes that the self-noise of the power module of the sensitive structure is one of the main factors affecting the self-noise level of the MEMS vector microphones. Therefore,a low-noise power supply module based on LT3045-1 is designed and fabricated in this paper. The tested self-noise level is close to lead-acid battery. Subsequently,the power module is applied to a MEMS vector microphone,which effectively improves the self-noise performance of the vector microphone. The self-noise level of the microphone is similar to that of MEMS vector microphone abroad,which realizes the optimization of domestically produced low noise vector microphones.

关 键 词：MEMS矢量传声器 质点振速 自噪声 低噪声电源 

分 类 号：TB526[理学—物理]