Abstract: A digital signal processing method is for enhancing fidelity of equivalent-time waveform measurements. The method includes receiving a digitized equivalent-time waveform of a repeating signal under test (SUT), applying a low-pass filter to the digitized equivalent-time waveform to obtain a smoothed waveform, generating a residual waveform by subtracting the smoothed waveform from the digitized equivalent-time waveform, estimating contributions of multiple noise sources in the residual waveform using a regression model, computing target noise and jitter values by removing known intrinsic contributions, and reconstructing a corrected waveform by combining the smoothed waveform with a scaled version of the residual waveform, wherein the scaling is based on the target noise source contributions.