Table 2.

List of linear, nonlinear, and time-frequency features extracted from electrohysterographic signals.

Linear	Nonlinear (Entropy-based)	Time-frequency (Wavelet)
Maximum Frequency (21)	Phase Entropy (PhEn) (22)	Flux 0° (12)
Medium Frequency (21)	Sample Entropy (SampEn) (23)	Flux 45° (12)
Root Mean Square (RMS) (24)	Dispersion Entropy (DispEn) (25, 26)	Flux 90° (12)
Zero-Crossing Rate (ZCR) (27)	Permutation Entropy (PerEn) (28, 29)	Energy (12)
Amplitude (21)	Bubble Entropy (bEn) (30, 31)	DWT (8)
	Fuzzy Entropy (FuzEn) (32)