IDFT of H(z) sampled in N values

1. How do you calculate Idft?
2. What is N in DFT formula?
3. What is the relation between DFT and Z-transform?

How do you calculate Idft?

The IDFT is defined as(11.4. 2)an≡1N∑m=1NAme2πin−1m−1N≡IDFTAmnfor n=1 to N.

What is N in DFT formula?

DFT[x1(n) N x2(n)] = X1(k)X2(k) Where N indicates N-point circular convolution. Multiplication property: If X1(k) = DFT[x1(n)] & X2(k) = DFT[x2(n)], then. DFT[x1(n)x2(n)] = (1/N)[X1(k) N X2(k)]

What is the relation between DFT and Z-transform?

Also, if r = 1, then the discrete time Fourier transform (DTFT) is same as the Z-transform. In other words, the DTFT is nothing but the Z-transform evaluated along the unit circle centred at the origin of the z-plane.