On-Face Antennas for Wearable Wireless Breath Monitoring

Portable breath monitoring systems that exploit wireless wearable devices can become game changers in the diagnosis and follow-up of healthy or chronically ill subjects as well as athletes. As opposed to conventional breath testing procedures, that must be performed in clinical settings and require the use of bulky instrument, a complete wireless and fully wearable breath measurement system is presented in this paper. The collection of the oscillatory temperature patterns produced by the ambient-lungs air exchange during respiration is carried out by a fully passive epidermal soft sensor that adheres close to the nostril. The wireless communication of the sensed data is then conveyed by a head-worn interrogating antenna, fitted a few centimeters away from the nose via a light ear-mounted bracket. Finally, an assessed post-processing procedure allows for the evaluation of some clinical-level respiratory parameters from the recorded signals. The preliminary test performed outdoor during physical exercise confirmed that such system can leave the user unhindered to perform their daily activities while an assessment of their respiratory function is carried out.