“…The fault feature extraction based on signal processing is one of the hot topics, where Hilbert-Huang Transform (HHT) [1], wavelet [2][3][4], and wavelet packet transform [5] can obtain the time-frequency features for fault diagnosis in analog circuits. Rényi's entropy [6], conditional entropy [4,7] and cross-wavelet singular entropy [8] are used for fault feature extraction, since the entropy can be used to measure the uncertainty and variation of information. In order to reflect the faulty information from different perspectives, the statistical properties of the fractional transform signals are proposed as the fault features [9], for example, distance, mean, standard deviation, skewness, kurtosis, entropy, median, third central moment, and centroid.…”