2. Methodology
2.1. Adaptive Filtering.
Conventional filtering cannot be applied to eliminate those types of artifacts because EEG signal and artifacts have overlapping spectra.
Herein, we propose the use of adaptive filters, which are based on the optimization theory. Adaptive filters have the capability of modifying their properties according to selected features of the signals being analyzed. Figure 2 illustrates the structure of an adaptive filter. There is a primary signal d(n) and a secondary signal x(n). The linear filter H(z) produces an output y(n), which is subtracted from d(n) to compute an error e(n).