Open Access

Wavelet-Based Algorithm for Signal Analysis

EURASIP Journal on Advances in Signal Processing20072007:038916

Received: 6 August 2006

Accepted: 24 November 2006

Published: 10 January 2007


This paper presents a computational algorithm for identifying power frequency variations and integer harmonics by using wavelet-based transform. The continuous wavelet transform (CWT) using the complex Morlet wavelet (CMW) is adopted to detect the harmonics presented in a power signal. A frequency detection algorithm is developed from the wavelet scalogram and ridges. A necessary condition is established to discriminate adjacent frequencies. The instantaneous frequency identification approach is applied to determine the frequencies components. An algorithm based on the discrete stationary wavelet transform (DSWT) is adopted to denoise the wavelet ridges. Experimental work has been used to demonstrate the superiority of this approach as compared to the more conventional one such as the fast Fourier transform.


Authors’ Affiliations

Division of Building Science and Technology, City University of Hong Kong
School of Engineering and Mathematical Sciences, City University


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© N. C. F. Tse and L. L. Lai. 2007

This article is published under license to BioMed Central Ltd. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.