We have already introduced the z-transform. Let us now introduce the properties of z-transform.
This property states that if then
where a1 and a2 are constants.
Let x(n) = a1x1(n) + a2x2(n)
The z-transform of x(n) is given by
Since the superposition principle is applicable to z-transform, it is linear and the ROC of X(z) is the overlap or intersection of the individual regions ...