What is DTFT formula?
The DTFT of the convolution sum of two signals x1[n] and x2[n] is the product of their DTFTs, X1(ejω) and X2(ejω). That is: y [ n ] = x 1 [ n ] * x 2 [ n ] ⇔ Y ( e j ω ) = X 1 ( e j ω ) X 2 ( e j ω ) .
How do you calculate DTFT of a signal?
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+...)
Why is DTFT used?
The DTFT is often used to analyze samples of a continuous function. The term discrete-time refers to the fact that the transform operates on discrete data, often samples whose interval has units of time.