(a) Plot the spectrum of a PAM wave produced by the modulating signal m (t) Am cos (2ipA?mt) assuming a modulation frequency A?m = 0.25 Hz, sampling period Ts = 1 s, and pulse duration T = 0.45 s.
(b) Using an ideal reconstruction filter, plot the spectrum of the filter output. Compare this result with the output that would be obtained if there were no aperture effect.