Question

The R.O.C. of impulse function is _________

(a) The entire z-plane

(b) Interior to the unit circle |z|=1

(c) Exterior to the unit circle |z|=1

(d) Between the unit circle |z|=1 and |z|=∞

I had been asked this question in an online interview.

The question is from Z Transform topic in chapter Digital Signal Processing of MATLAB

Answer 1

Right option is (a) The entire z-plane

The explanation: The impulse function has a Z-transform equal to 1.Since it is independent of z, it exists for all values of z. Hence, the Z-transform converges for all values of z. Thus, the R.O.C. of impulse function is the entire z-plane.