Complex higher order spectra vs. it's magnitude for nondestructive testing of nonlinearity in structures

L. Gelman, S. Yakasai

Research output: Contribution to journalArticle

2 Citations (Scopus)


This technical brief compares experimentally the use of complex higher order spectra (HOS) and HOS magnitude for nondestructive testing (NDT) of nonlinearity level of the structure. Normally, the nonlinearity level of the structure is changed due to structure damage. The HOS of order is the complex valued function and proportional to the multiplication of Fourier transforms of signal components. The study demonstrates that the use of complex HOS is more efficient for nonlinearity NDT due to the following two reasons: (i) complex HOS contains both amplitude and phase information of HOS whereas the magnitude of HOS contains only amplitude information; and (ii) usage of HOS components allows constructing optimal decision-making rule.

Original languageEnglish
Pages (from-to)103-107
Number of pages5
JournalNondestructive Testing and Evaluation
Issue number2
Early online date23 Nov 2006
Publication statusPublished - 2006
Externally publishedYes


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