“…In MCSA, the signal conditioning stage may include windowing [4], filtering, frequency displacement [5], elimination of negative frequencies [6], etc. Spectral analysis may be performed with a variety of mathematical tools, such as the Fourier transform (FT) [7]- [10], multiple signal classification [8], maximum covariance methods [11], [12], and others [13]. Finally, a threshold level is established that is based on either the amplitude [7], [14] or the phase of the characteristic fault harmonics, as given in (1) and (2), to diagnose the presence or the absence of a fault.…”