Noncontact Respiration Rate Measurement System Using an Ultrasonic Proximity Sensor

Abstract

This research presents the ultrasonic proximity sensor approach to respiration measurement. The ultrasonic proximity sensor measures respiration signatures and rates in real-time and for long-term monitoring, which is necessary for mobility from the end-user perspective. The study used a 240 kHz ultrasonic sensor to measure the time of flight of a sound wave between the transmitted signal and received signal during respiration in the abdominal wall-motion. Respiration rates measured with the ultrasonic proximity sensor were then compared with those measured with a thermocouple sensor on ten male subjects. Data from the measurement of respiration rates at 100 cm is provided. We have used this data from the method comparison study to confirm agreement with the reference signal to determine that the current version of respiratory rate detection system using ultrasonic can successfully measure respiration rates. The proposed respiratory measurement method could be used to monitor an unconscious person without the need to apply electrodes or other sensors in the correct position and to wire the subject to the system. Monitoring respiration using ultrasonic sensor offers a promising possibility of noncontact measurement of respiration rates. In particular, this technology offers a potentially inexpensive means to extend applications to consumer home-healthcare and mobile-healthcare products. Further advances in the sensor design, system design and signal processing can increase the range and quality of the measurement, broadening the potential application areas of this technology.