“…Another term of comparison for the different diagnostic approaches is the signal processing technique used in their implementation. Fast Fourier Transform (FFT) [22][23][24][25], Short Time Fourier Transform (STFT) [26,27], Discrete Wavelet Transform (DWT) [4,10,11,21,26,[28][29][30][31][32][33][34], Stationary Wavelet Transform (SWT) [35][36][37][38], Dual-Tree Complex Wavelet Transform (DTCWT) [4,34], Wavelet Packet Transform (WPT) [39][40][41], Rational-dilation Wavelet Transform (RADWT) [42], Artificial Intelligence (AI) [43,44], Kalman filter [45,46] and Hilbert-Huang Transform (HHT) [47][48][49] are some of the techniques presented in the literature.…”