The Higher Order Spectra for Condition Monitoring/ndt in Non-stationary Conditions:
نویسندگان
چکیده
The classical multi-frequency higher order spectra (HOS) based on the Fourier transform has been widely investigated for nonlinearity detection in stationary temporal processes. However, for some important applications (e.g. radar and sonar systems, mechanical systems with transient shaft rotation, etc.) it is necessary to process transient temporal processes with any (i.e. linear and nonlinear) polynomial variation of the instantaneous frequency. The classical HOS is not suitable for these processes because
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