Title
Monitoring Breathing via Signal Strength in Wireless Networks
Abstract
This paper shows experimentally that standard wireless networks which measure received signal strength (RSS) can be used to reliably detect human breathing and estimate the breathing rate, an application we call “BreathTaking”. We present analysis showing that, as a first order approximation, breathing induces sinusoidal variation in the measured RSS on a link, with amplitude a function of the relative amplitude and phase of the breathing-affected multipath. We show that although an individual link may not reliably detect breathing, the collective spectral content of a network of devices reliably indicates the presence and rate of breathing. We present a maximum likelihood estimator (MLE) of breathing rate, amplitude, and phase, which uses the RSS data from many links simultaneously. We show experimental results which demonstrate that reliable detection and frequency estimation is possible with 30 seconds of data, within 0.07 to 0.42 breaths per minute (bpm) RMS error in several experiments. The experiments also indicate that the use of directional antennas may improve the systems robustness to external motion.
Year
DOI
Venue
2014
10.1109/TMC.2013.117
Mobile Computing, IEEE Transactions  
Keywords
Field
DocType
directive antennas,frequency estimation,maximum likelihood estimation,medical signal processing,patient monitoring,pneumodynamics,wireless sensor networks,breathing rate,directional antennas,first order approximation,frequency estimation,human breathing monitoring,maximum likelihood estimator,received signal strength,systems robustness,wireless networks,Emerging technologies,Network monitoring,Sensor networks,Wireless communication,Wireless sensor networks,health care,radio propagation,sensing,statistical signal processing
Wireless network,Wireless,Computer science,Computer network,Respiratory rate,Breathing,Network monitoring,Statistical signal processing,Wireless sensor network,Radio propagation
Journal
Volume
Issue
ISSN
13
8
1536-1233
Citations 
PageRank 
References 
32
2.44
7
Authors
4
Name
Order
Citations
PageRank
Neal Patwari13805241.58
J R Wilson2423.19
S. Ananthanarayanan3322.44
Sneha Kumar Kasera432618.78