Infinite Impulse Response

Infinite Impulse Response

Infinite impulse response (IIR) is a property of signal processing systems. Systems with this property are known as IIR systems or, when dealing with filter systems, as IIR filters. IIR systems have an impulse response function that is non-zero over an infinite length of time. This is in contrast to finite impulse response (FIR) filters, which have fixed-duration impulse responses. The simplest analog IIR filter is an RC filter made up of a single resistor (R) feeding into a node shared with a single capacitor (C). This filter has an exponential impulse response characterized by an RC time constant. Because the exponential function is asymptotic to a limit, and thus never settles at a fixed value, the response is considered infinite.

Read more about Infinite Impulse Response:  Implementation and Design, Transfer Function Derivation, Description of Block Diagram, Stability, Example, Applications

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