User Portlet User Portlet

Discussions
Consider a signal x(k) with sampling time Tc =1, then its Discrete Fourier Transorm is X(f). If now I have to consider y(k) that is the upsapled version of the signal x(k),  with sampling time Tc = 1/4,  (meaning y(k) = x(k) for T=4*k, y(k)=0...