Using the given identities, find the inverse DTFT

1. What is inverse DTFT?
2. How do you find DTFT?
3. How do you find DTFT from DFT?

What is inverse DTFT?

The inverse DTFT is the original sampled data sequence. The inverse DFT is a periodic summation of the original sequence. The fast Fourier transform (FFT) is an algorithm for computing one cycle of the DFT, and its inverse produces one cycle of the inverse DFT.

How do you find DTFT?

Find the DTFT of the sequence x(n)=u(n−k). ⇒F[u(n−k)]=e−jωk+e−jω(k+1)+e−jω(k+2)+... ⇒F[u(n−k)]=e−jωk(1+e−jω+e−j2ω+e−j3ω+...)

How do you find DTFT from DFT?

Correct Answer: Theoretical, Continuous-ω 2π-Periodic DTFT can be obtained by continuous Lagrangian-interpolation of the DFT Samples. So that the values at ω=2πk/N will be the DFT Samples X[k] for k=0,1,...,N−1 and the Interpolation-function's zero-crossings are at 2πk/N.