多通道肺音采集系统设计

Design of a Multi-channel Lung Sound Data Acquisition System

目的:设计一种多通道肺音采集系统。方法:系统采用增强型的32位基于ARM核心的微控制器STM32F103ZET6作为核心控制芯片。电容传声器将采集到的肺音信号转换为电信号,设计多路放大滤波电路对肺音电信号进行处理,微控制器通过控制4通道串行输出AD转换芯片ADS8341实现多通道数据采集,采用SD卡作为存储介质用以存储所采集的肺音信号,采用液晶显示器作为人机界面,显示操作提示信息或系统工作状态。结果:可以同时采集1-4通道的肺音数据,采样频率为8789 Hz,数据采样精度为16位,单次可连续存储30s^60s的肺音数据。结论:系统操作简便,体积较小,肺音数据以WAV格式的音频文件存储于SD卡中。计算机可以方便地读取SD卡中肺音数据,进行肺音音频播放,还可以对肺音数据进行进一步的分析处理。系统能准确地采集多通道肺音数据,数据存储快速、可靠,数据读取方便,能满足临床医生采集肺音数据的需求。

Objective： To design a multi-channel lung sound data acquisition system. Methods： An enhanced 32 bit ARM microcontroUers STM32F103ZET6 was used as the core control chip in the data acquisition system. The lung sounds collected by the condenser microphones were translated into electrical signal and were amplified by the multi-channel amplifier and filter circuits. The 4- channel 16 bit serial AD converter ADS8341 was used to realize the multi-channel data acquisition controlled by the microcontroller. The SD card was used as storage medium to store the lung sound data. The Liquid crystal display was used as the man-machine interface to display system message. Results： It could be used to collect 1 to 4 channels of lung sounds at the same time. The sampling rate was 8789 Hz and the resolution of data was 16 bit. It could save 30 seconds or 60 seconds of lung sound data in a single trial. Conclusions： The system is easy to operate and small in size. The lung sound data were stored as WAV format audio files in the SD card. The lung sound data in the SD card can be easily read by the computers for audio playback or data analysis. The system can collect multi-channel lung sound accurately. Data can be stored quickly and safe and be read easily, which satisfy the need of doctors to collect lung sound.