Development Of Remote Heart Sound Auscultation System Based On Dual-microphone Filtering

With the acceleration of the population aging,the cardiovascular disease has become one of the most common diseases.Auscultation is an essential clinical diagnostic method for cardiovascular diseases.However,there are some deficiencies and limitations in the current heart sound auscultation services for family users,traditional hospitals and Internet medical institutions.In addition,the limitation of time and space in traditional way to go to hospital leads to cumbersome process and high cost.With the rapid development of mobile Internet,sensor technology and big data technology,the emergence and development of remote auscultation has become an inevitable trend.This paper develops a remote heart sound auscultation system based on dual-microphone filtering from the view of cost,portability and anti-noise ability.It mainly provides services for network hospitals,family users and community hospitals to solve the difficulties of remote collection of heart sound data.And it can improve the convenience of telemedicine and reduce the cost of clinical diagnostic.The main contents include:Firstly,based on the characteristics of the heart sound signal,this paper designs the hardware acquisition system of the electronic stethoscope based on STM32,which is mainly used to collect and amplify the weak heart sound without distortion.The hardware system includes stethoscope chest piece,signal collection circuit,signal conditioning circuit,main control circuit,Bluetooth circuit and power supply circuit.Secondly,two Android APPs have been developed for patients and doctors,which are used to perform the functions of heart sound acquisition,cloud upload,doctor diagnosis and feedback of auscultation results.In addition,the control system program of the STM32 lower machine is designed,including STM32 peripheral driver,ADC sampling program and Bluetooth communication protocol.Finally,this paper designs an adaptive filtering algorithm based on dual-microphone to reduce the interference of environment noise that is difficult to avoid in the remote heart sound auscultation.It can improve the clarity and accuracy of the heart sound signal and ensure the effectiveness of the remote auscultation.At the same time,the effectiveness and practicability of the algorithm are verified by simulation experiments and examples.The experimental results show that the algorithm can filter some ambient noise.