1. A digital filter is described by the following difference equation. determine if this is an IIR or FIR filter. Explain your answer.

Question

Y[n] = 0.25x[n] + 0.5x[n-1] + 0.25x[n-2] - 1.2y[n-1] + 0.2y[n-2]

Filter Type:
a) IIR filter
b) FIR filter

Answer 1

This is an IIR filter. An IIR (Infinite Impulse Response) filter is a type of digital filter that has feedback in its difference equation, resulting in the possibility of an infinite response to a finite input. In this equation, the presence of terms involving y[n-1] and y[n-2] indicates feedback, which is characteristic of an IIR filter.