Fig. 1
From: Improved shift-invariant sparse coding for noise attenuation of magnetotelluric data
Results of pseudo-random square-wave noise processing. a Original noise-free MT signal; b the synthetic noisy signal; c de-noised by square-wave dictionary-based method (IOMP-SD); d de-noised by ISISC. The left panels are time domain waveforms and the right panels are their spectra