Experimental Mechanics

, Volume 41, Issue 4, pp 324–331 | Cite as

Spectrotemporal analysis of guided-wave pulse-echo signals: Part 1. Dispersive systems

  • S. -C. Wooh
  • K. Veroy


In this paper, a wavelet-based time frequency analysis is presented to analyze guided-wave signals for rapid inspection of thin-walled structural members. The overall objective is to detect and locate discontinuities using a single broadband signal. Part 1 of this paper shows how the wavelet transform can be used to analyze a dispersive system. A straightforward procedure is developed to extract group delay information from the computed wavelet transform coefficients. The procedure is demonstrated by a simulation study for single-mode and simple dual-mode dispersion signals. Part 2 is an experimental study of multimode dispersion.

Key Words

Guided waves multimode dispersion wavelet transform group delays bandwidth 


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Copyright information

© Society for Experimental Mechanics, Inc. 2001

Authors and Affiliations

  • S. -C. Wooh
    • 1
  • K. Veroy
    • 1
  1. 1.Department of Civil and Environmental EngineeringMassachusetts Institute of TechnologyCambridge

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