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digital filter

An LTI system deliberately designed to reshape a signal's frequency content -- passing some frequencies through and attenuating others.

A digital filter is an LTI system built for the specific purpose of filtering -- reshaping a signal's frequency content by passing some frequencies through largely unchanged while attenuating or removing others. FIR and IIR systems are the two families this course designs filters from.

See also

LTI system FIR system IIR system
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