Research And Development Of Laryngeal Respiratory Detection System Based On Digital Signal Processing Technology

In the process of human respiration,the mucous membrane of the respiratory tract secretes mucus to capture a variety of bacteria,dust and inflammatory cells and other harmful substances,which will form viscous sputum.Critical patients in the process of using the ventilator,can not consciously spit out the sputum,with the passage of time,the throat of the sputum will gradually accumulate,resulting in a reduction in oxygen intake,adverse effects on patient treatment.In order to reduce the negative effects of sputum,the relevant research was carried out and the key technologies involved were summarized,the advantages and disadvantages of the existing schemes were pointed out,and then a new research scheme was proposed.According to the characteristics of respiratory sounds of patients,a throat respiratory detection system based on timedomain analysis technology is developed.The system can detect the breathing condition of patients’ throat in real time.When the amount of sputum accumulates to affect breathing,the medical staff will be informed immediately to draw out the sputum.The main research contents include:(1)Development of wireless electronic audio collector:1)Hardware design: mainly includes the design of contact microphone circuit based on PVDF film and the design and implementation of audio acquisition and wireless transmission circuit based on ESP32 chip.2)Software design: application software development based on Free-RTOS,mainly including the design and implementation of audio coding module program,audio data transmission program,and instruction receiving module program.(2)Research and implementation of breath detection algorithm: digital bandpass filtering based on audio and short-time energy analysis algorithm can realize real-time diagnosis of breath sound condition,and judge whether the patient’s throat sputum needs to be cleaned according to the breathing condition.(3)The design and implementation of the upper computer software based on Python: the upper computer software was developed based on Python language to analyze and process the breathing sound signal collected by wireless electronic audio,and the auxiliary diagnostic function,notification function,audio data compression and preservation function and breathing sound wave shape display function were realized.The experimental results show that the system can accurately determine whether the sputum of the patient’s throat needs to be sucked out and timely inform the medical staff to deal with it,which has a certain application value.The respiratory detection system developed in this paper is low-cost and easy to deploy,which is suitable for telemedicine,smart medicine,mobile medicine,medical teaching and other scenarios.