Question

An IIR system with system function H(z)=\(\frac{B(z)}{A(z)}\) is called a minimum phase if ___________

(a) All poles and zeros are inside the unit circle

(b) All zeros are outside the unit circle

(c) All poles are outside the unit circle

(d) All poles and zeros are outside the unit circle

I have been asked this question during an interview.

My question is taken from Inverse Systems and Deconvolution topic in chapter Frequency Analysis of Signals and Systems of Digital Signal Processing

Answer 1

Right answer is (a) All poles and zeros are inside the unit circle

For explanation I would say: For an IIR filter whose system function is defined as H(z)=\(\frac{B(z)}{A(z)}\) to be said a minimum phase,

then both the poles and zeros of the system should fall inside the unit circle.