
85-1
85.1 Introduction
In its broadest sense, a lter can be dened as a signal-processing system whose output signal, usually
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some prescribed properties. In more practical terms, an electric lter is a device designed to suppress,
pass, or separate a group of signals from a mixture of signals according to the specications in a par-
ticular application. e application areas of ltering are manifold, for example to band-limit signals
before sampling to reduce aliasing, to eliminate unwanted noise in communication systems, to resolve
signal ...