Application of Wavelet and EEMD Joint Denoising in Nonlinear Ultrasonic Testing of Concrete

Table 2

Characteristic indicators of the signal after wavelet threshold denoising.

SNR	RMSE	Amplitude of the fundamental A1 (mV)	Amplitude of the second harmonic A2 (mV)	Relative error A1 (%)	Relative error A2 (%)	Relative error (%)
10.98	20.00	9288	1800	1.28	10.23	13.09