Release Time:2019-03-09 Hits:
Indexed by: Journal Article
Date of Publication: 2010-02-01
Journal: IEEE TRANSACTIONS ON BIOMEDICAL ENGINEERING
Included Journals: Scopus、SCIE、PubMed
Volume: 57
Issue: 2
Page Number: 325-333
ISSN: 0018-9294
Key Words: Cycle-frequency domain; cyclic stationarity enhancement; disturbance reduction; heart sounds; noise reduction; nonlinear time scaling
Abstract: Through an investigation of various clinical cases, heart sounds are found to be quasi-cyclostationary. Nonlinear time scaling from cycle-to-cycle is proposed to enhance cyclic stationarity, where nonlinear time scaling is approximated by a piecewise linear function. The techniques of cyclostationary signal processing are employed in this paper to reduce noise and disturbance in the cycle-frequency domain. Heart sounds can be theoretically recovered in the presence of additive, zero mean noise, and disturbance (perhaps non-Gaussian, nonstationary, or colored). The experimental tests in various conditions confirm the theoretical results.