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  • Research Article
  • 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:


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.


  • Fast Fourier Transform
  • Detection Algorithm
  • Frequency Component
  • Identification Approach
  • Power Signal

Authors’ Affiliations

Division of Building Science and Technology, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong
School of Engineering and Mathematical Sciences, City University, Northampton Square, London, EC1V0HB, UK


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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.