基于MEMS麦克风阵列的定向拾音系统设计  

Design of Directional Sound-Capture System based on MEMS Microphone Array

作　　者：张政 许向阳[1] 王晓琳[2] 吴鸣[2] 韩欣宇 ZHANG Zheng;XU Xiang-yang;WANG Xiao-lin;WU Ming;HAN Xin-yu(School of Information Science and Engineering,Hebei University of Science and Technology,Shijiazhuang Hebei 050018,China;Key Laboratory of Noise and Vibration,Institute of Acoustics,Chinese Academy of Sciences,Beijing 100190,China)

机构地区：[1]河北科技大学信息科学与工程学院,河北石家庄050018 [2]中国科学院声学研究所噪声与振动重点实验室,北京100190

出　　处：《通信技术》2018年第9期2241-2246,共6页Communications Technology

摘　　要：设计了一种基于MEMS麦克风和FPGA、DSP的阵列定向拾音系统。麦克风为楼氏公司的型号为SPM0423HD4H-WB的MEMS麦克风。该麦克风内部集成Sigma-Delta ADC,使用方便,灵敏度高,抗干扰性强。FPGA内部可实现CIC滤波器对麦克风输出信号的降采样处理,并且拥有丰富的IO口资源,适用于对多元阵列进行数据采集。因此,系统的拾音部分设计了一个使用MEMS麦克风的6×6的36通道平面阵列。另外,系统采用TI公司的TMS320C6647高性能定点/浮点DSP作为数字信号处理的核心单元,使用DSP的EMIF接口对FPGA内部采集的数据进行处理,同时EDMA进行数据的传输控制。实验证明,该系统采集数据量大,工作稳定可靠,具有很高的传输速率,适用于多通道麦克风阵列的定向拾音,可为麦克风阵列的应用提供帮助。An array-oriented sound capture system based on MEMS microphone,FPGA and DSP is designed.Microphone is a MEMS microphone of SPM0423HD4H-WB model from KNOWLES ELECTRONICS Company.The microphone,with inside integration of Sigma-Delta ADC,is easy to use,high in sensitivity and strong in anti-interference.The CIC filter inside the FPGA can downsample the signal output from the microphone,and has rich IO port resources for data collection on multiple arrays.Therefore,the pickup portion of the system is designed with a 6×6 36-channel planar array with MEMS microphone.In addition,the system adopts TI's TMS320C6647 high-performance fixed-point/floating-point DSP as the core unit of digital signal processing,DSP's EMIF interface for processing the data collected inside the FPGA,and EDMA for data transmission control.Experiments indicate that this system could collect large amount of data,work stably and reliably,and has fairly high transmission rate,thus is suitable for directional pickup of multi-channel microphone arrays and may provide assistance for the application of microphone arrays.

关 键 词：MEMS麦克风阵列 定向拾音 脉冲密度调制 FPGA DSP 级联积分梳妆滤波器 外部存储器接口 

分 类 号：TN406[电子电信—微电子学与固体电子学]