Question

Explain the concept of ROC in Z transform.

Answer 1

The ROC cannot contain any poles.B y definition a pole is awhereX(z) is infinite.Since X(z) must be finite for all z for convergence,t here cannot be a pole in the ROC.If x(n)is afinite-duration sequence,then the ROC is the entire z-plane,e except possibly z=0
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