Respiratory Monitoring System Based On Halide Perovskite Humidity Sensor

In morden socity,the pace is fast,great life and work pressure lead to many peoples have sleep peoblems,includes Sleep Apnea Syndrome,which is noamal,harmful but diffclut to diagnose.Now,Sleep Apnea Syndrome dignose by polysomnography,but this method need device which large and expensive,only can diagnose in professional test room,when in testing,patient will feel uncomfortable because many electrode and wire attach on patient body.So,it is great significance to develop a respiratory function monitoring system which portable,simple structure,low cost and can wireless transmission signal.Breathing airflow is the most direct reflection of breath movement,which has 30 percent humidity difference with surrounding environment,use it to monitor respiratory function has signal process simple,low cost and result is reliable.A breath cycle from 3to 5 seconds,market humidity sensor which response and recovery time varies from tens of seconds to several minutes,cannot meet the respiratory signal measurement.The inorganic halide perovskite humidity sensor developed in this paper,can be used for the measurement of respiratory and nasal airflow signals when the humidity changes 30 percente,the resistance of the sensor will change significantly and recover within 3 seconds.The system use Zigbee network transmit signal for use expediently.In order to facilitate the tester to observe the test situation and automatically process the respiratory signals,the corresponding upper computer software was developed.In order to process the signal in real time,the maximum value of respiratory signal was extracted by the extremum iteration method,and the threshold values of apnea and hypopnea were calculated by the dynamic threshold method.By testing the monitoring system,the collection,transmission and reception of respiratory airflow signals can be realized.Combined with the upper computer software,the predetermined respiratory function monitoring can be realized.To tset this system stability shows this system have strong adaptation to different sensor location.In different breath intensity and frequnency,this system can relize respiratory function monitoring.Testing prove self-develop humidity sensor which adopt in this system can meet airflow signal measure.This system can process breath signal real time and judge breath condition,which posess non-contact,strong real time,wireless and lowcost advantage.