Discrete-Time Fourier Transform Its dtfT is given by X(e0)=∑a' u[n]e j=∑a'e-~0n n=-0 n=0 =∑ejoy=e/o n=0 as ae Jo=a<1 10 Copyright C 2001, S K MitraCopyright © 2001, S. K. Mitra 10 Discrete-Time Fourier Transform • Its DTFT is given by as =   =   = − w  =− w − w 0 ( ) [ ] n n j n n j n j n X e n e e − w −  = − w =   = j e n j n e 1 1 0 ( )  =  1 − jw e