Phase tracking of the breathing cycle in sleeping subjects by frequency analysis of acoustic data
by Hisham Alshaer, Geoffrey R. Fernie, T. Douglas Bradley
International Journal of Healthcare Technology and Management (IJHTM), Vol. 11, No. 3, 2010

Abstract: We tested the hypothesis that the inspiratory and expiratory phases of breathing could be identified from breath sound recordings during sleep. Breath sounds were digitally recorded from 10 subjects during sleep. Frequency spectra of inspiration and expiration were determined. The ratio of frequency magnitude bins between 400-1000 Hz to frequency bins between 10-400 Hz was calculated for inspiration (Ri) and expiration (Re) for each breath. The Ri/Re ratio was significantly greater than the thresholds of 1.5 (p < 0.001) and 2-fold (p < 0.001). Breathing phases were correctly identified in 90% and 73% of cases using the 1.5 and 2.0 thresholds, respectively.

Online publication date: Mon, 12-Jul-2010

The full text of this article is only available to individual subscribers or to users at subscribing institutions.

Existing subscribers:
Go to Inderscience Online Journals to access the Full Text of this article.

Pay per view:
If you are not a subscriber and you just want to read the full contents of this article, buy online access here.

Complimentary Subscribers, Editors or Members of the Editorial Board of the International Journal of Healthcare Technology and Management (IJHTM):
Login with your Inderscience username and password:

    Username:        Password:         

Forgotten your password?

Want to subscribe?
A subscription gives you complete access to all articles in the current issue, as well as to all articles in the previous three years (where applicable). See our Orders page to subscribe.

If you still need assistance, please email