Definition of a Digital Filter
Logic circuits create a digital filter by introducing a digital signal at the system's input and modifying it at the output. The temporal supports of the two signals, both at the input and output, are defined by specific sequences. Various types of digital filters exist, including low-pass, high-pass, band-pass, band-reject, integrator, and differentiator filters. Replicating most analog filters as digital filters is noteworthy.
Figure 4: The digital filter and the analogue filter.