Title
WiRelax: Towards real-time respiratory biofeedback during meditation using WiFi
Abstract
Respiratory pattern tracking proved to be critical for many applications ranging from well-being monitoring and stress management to dealing with chronic breathing abnormalities. Specific breathing and meditation exercises have been designed to improve well-being of users based on monitoring the complete breathing waveform. While wearable systems had leveraged a wealth of information available from respiration stream in a variety of applications, contact-less sensing systems are lagging behind when it comes to capturing detailed breathing metrics. In this work we propose WiRelax; the first non-contact respiratory biofeedback system that relies solely on WiFi availability. We propose algorithms that map the changes in the Channel State Information (CSI) to the instantaneous breathing state. The key contribution is a model that relates relative phase of the received signal and the micro-motion of the chest during breathing. A novel processing pipeline is developed to extract a single breathing waveform from CSI data captured across noisy multiple sub-carriers in real-time. Our evaluation in a real-world setup shows that WiRelax can estimate real-time breath-by-breath cycle time with median error less than 0.25 s ( < 13% relative to the cycle length) thus enabling accurate device-free respiratory biofeedback.
Year
DOI
Venue
2020
10.1016/j.adhoc.2020.102226
Ad Hoc Networks
Keywords
DocType
Volume
Biofeedback,Breathing,WiFi,Device-free
Journal
107
ISSN
Citations 
PageRank 
1570-8705
0
0.34
References 
Authors
0
4
Name
Order
Citations
PageRank
Abdelwahed Khamis141.49
Brano Kusy2608.48
Chun Tung Chou3119790.98
Wen Hu41373104.78