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Demodulation methods are one of the most widely used tools for bearing diagnostics, and in particular, are methods based on the Squared Envelope Spectrum (SES) with band pass filtering. One of the main challenges of these methods is the detection of a suitable band for the demodulation of the signal under varying speed conditions. Angular resampling methods may

Rolling element bearing fault diagnostics has been a topic of intensive research.As the rolling element bearings are a critical component of rotating machinery, failure of these components results in the breakdown of the mechanical structure in which they operate. The correct detection of incipient faults on the bearings can reduce the production cost by allowing maintenance engineers to schedule a replacement at the most convenient time. Envelope analysis is a widespread method in bearing diagnostics, where the frequency band that carries the fault information is detected and amplitude demodulated to obtain the envelope, whose spectrum reveals the repetition frequencies of the particular fault. It is often used along with Fast Kurtogram, which selects this band based on the kurtosis level. However, this methodology shows difficulty in selecting the correct band on complex signals. Signals contaminated with Electro-Magnetic Interference (EMI) are one such example where Envelope Analysis based on the Fast Kurtogram (FK) often fails to diagnose bearing faults. EMI is often present in mechanisms whose motor is controlled by a Variable-Frequency Drive (VFD), and shows a behaviour similar to that of bearing faults, and thus increases the

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