Next Article in Journal
Directional Navigation Improves Opportunistic Communication for Emergencies
Next Article in Special Issue
Non-Destructive Evaluation of Depth of Surface Cracks Using Ultrasonic Frequency Analysis
Previous Article in Journal
Intra-and-Inter Species Biomass Prediction in a Plantation Forest: Testing the Utility of High Spatial Resolution Spaceborne Multispectral RapidEye Sensor and Advanced Machine Learning Algorithms
Previous Article in Special Issue
Wave Dispersion and Attenuation on Human Femur Tissue
Open AccessArticle

An Ultrasonic Contactless Sensor for Breathing Monitoring

Laboratoire PROTEE EA3819, Université de Toulon, Avenue de l'Université, BP 20132, La Garde Cedex, France
Clinical Research Unit, Centre Hospitalier Intercommunal de Toulon La Seyne. 54, rue Henri Sainte Claire Deville, BP 1412, 83056, Toulon Cedex, France
Laboratoire LSIS CNRS UMR 7296, Université de Toulon, Avenue de l'Université, BP 20132, La Garde Cedex, France
Author to whom correspondence should be addressed.
Sensors 2014, 14(8), 15371-15386;
Received: 10 June 2014 / Revised: 2 August 2014 / Accepted: 5 August 2014 / Published: 20 August 2014
The monitoring of human breathing activity during a long period has multiple fundamental applications in medicine. In breathing sleep disorders such as apnea, the diagnosis is based on events during which the person stops breathing for several periods during sleep. In polysomnography, the standard for sleep disordered breathing analysis, chest movement and airflow are used to monitor the respiratory activity. However, this method has serious drawbacks. Indeed, as the subject should sleep overnight in a laboratory and because of sensors being in direct contact with him, artifacts modifying sleep quality are often observed. This work investigates an analysis of the viability of an ultrasonic device to quantify the breathing activity, without contact and without any perception by the subject. Based on a low power ultrasonic active source and transducer, the device measures the frequency shift produced by the velocity difference between the exhaled air flow and the ambient environment, i.e., the Doppler effect. After acquisition and digitization, a specific signal processing is applied to separate the effects of breath from those due to subject movements from the Doppler signal. The distance between the source and the sensor, about 50 cm, and the use of ultrasound frequency well above audible frequencies, 40 kHz, allow monitoring the breathing activity without any perception by the subject, and therefore without any modification of the sleep quality which is very important for sleep disorders diagnostic applications. This work is patented (patent pending 2013-7-31 number FR.13/57569). View Full-Text
Keywords: breath monitoring; ultrasound; contactless; Doppler effect breath monitoring; ultrasound; contactless; Doppler effect
MDPI and ACS Style

Arlotto, P.; Grimaldi, M.; Naeck, R.; Ginoux, J.-M. An Ultrasonic Contactless Sensor for Breathing Monitoring. Sensors 2014, 14, 15371-15386.

Show more citation formats Show less citations formats

Article Access Map by Country/Region

Only visits after 24 November 2015 are recorded.
Back to TopTop