Development And Implementation Of Adaptive Noise Reduction Heart Sound Auscultation System

Stethoscope is of great significance for the non-invasive diagnosis of cardiovascular diseases,respiratory diseases and digestive diseases.The emergence of high-end diagnostic instruments and new diagnostic methods has reduced the status of stethoscope,but stethoscope has the advantages of simple operation,mature stethoscope theory,low cost,and is still widely used in medical diagnosis.With the development of the times and technology,it is difficult for traditional acoustic stethoscopes to meet people’s requirements.In order to enhance its performance and function,the stethoscope needs to be electronic,wireless,digital,and intelligent.Based on the existing research of our team,aiming to improve the hardware design of the electronic stethoscope and the performance of the noise reduction algorithm,and considering power consumption,cost,portability,immunity and fidelity,this paper develops a wireless auscultation system suitable for homes and hospitals,which is composed of a wireless electronic stethoscope and supporting auxiliary auscultation software.The main contents include:1)Based on STM32 chip and bluetooth module,a wireless electronic stethoscope is designed,which includes stethoscope head,hardware circuit and master program of lower computer,and it can realize the collection and wireless transmission of cardiopulmonary sound.2)Based on the Android platform,the supporting auxiliary auscultation software is designed to receive body sound signals collected by the electronic stethoscope in real time and reduce environmental noise interference.It can realize real-time auscultation,heart rate calculation,and file management.3)According to the characteristics of heart sound signal and environmental noise,an improved dual-microphone adaptive filtering algorithm is designed,which can filter out the environmental noise in the process of heart sound auscultation in real time,improve the algorithm convergence speed and steady-state performance,reduce the calculation complexity,and ensure that the heart sound has a high protection Truthfulness.This paper tests the performance of the wireless auscultation system through experiments and checks the effectiveness of the improved dual microphone adaptive filtering algorithm.