Question

a. What is the significance of the name IIR in the IIR filter? b. How negative feedback is more stable than positive feedback? c. FIR filter described by the difference equation y(n)=x[n]+3x[n-2]+6x[n-31+ 3x [n-1] i. Find the transfer function and order of the system ii. What is the term FIR signifies? [5 Marks] A video processing system internally performs filtering operation using IIR filter defined by the transfer function 1+ 4z-1 + z-2 1- 1.52-2 -0.093752-3 Find the poles and zeros of the system and also find whether the system is stable or unstable ii. Find the difference equation of the system. iii. How to differentiate FIR and IIR filter based on the difference equation. (5Marks

Answer 1

a.IIR filters are one of two primary types of digital filters used in Digital Signal Processing (DSP) applications (the other type being FIR). “IIR” means “Infinite Impulse Response.”The impulse response is “infinite” because there is feedback in the filter; if you put in an impulse (a single “1” sample followed by many “0” samples), an infinite number of non-zero values will come out (theoretically.)

b.Negative feedback system reduces the error between input and output.and it is always kept within the prescribed limits.

C.ii. A finite impulse response FIR filter is a filter whose impulse response is of finite duration, because it settles to zero in finite time

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