Question

Which of the following is true when the response of the single pole filter is in the limit cycle?

(a) Actual non-linear system acts as an equivalent non-linear system

(b) Actual non-linear system acts as an equivalent linear system

(c) Actual linear system acts as an equivalent non-linear system

(d) Actual linear system acts as an equivalent linear system

I had been asked this question in exam.

I need to ask this question from Round Off Effects in Digital Filters in portion Digital Filters Design of Digital Signal Processing

Answer 1

Right answer is (b) Actual non-linear system acts as an equivalent linear system

Explanation: We note that when the response of the single pole filter is in the limit cycle, the actual non-linear system acts as an equivalent linear system with a pole at z=1 when the pole is positive and z=-1 when the poles is negative.