Question

The z-transform of a signal x(n) whose definition is given by \(X(z)=\sum_{n=0}^{\infty} x(n)z^{-n}\) is known as _____________

(a) Unilateral z-transform

(b) Bilateral z-transform

(c) Rational z-transform

(d) None of the mentioned

I have been asked this question in quiz.

My question is taken from One Sided Z Transform topic in portion Z Transform and its Application – Analysis of the LTI Systems of Digital Signal Processing

Answer 1

The correct option is (a) Unilateral z-transform

For explanation I would say: The z-transform of the x(n) whose definition exists in the range n=-∞ to +∞ is known as bilateral or two sided z-transform. But in the given question the value of n=0 to +∞. So, such a z-transform is known as Unilateral or one sided z-transform.