Effect of Frequency Scaling:
The Inverse Fourier Transform of Y(w) = X(cw) is y(t) = |1/c| x(t/c).
Therefore the time signal corresponding to the frequency scaled spectra
|Y(w)| = |X(cw)|
<Y(w) = <X(cw)
is
y(t) = |1/c| x(t/c)
Compare the magnitude spectrum of X(w) with the
scaled magnitude spectrum of Y(w) = X(2w)
and the phase spectrum of X(w) with the scaled phase
spectrum of Y(w) = X(2w)
to the corresponding time signals
x(t) = e-tu(t)
y(t) = (1/2)x(t/2) = (1/2)e-t/2u(t/2)
= (1/2)e-t/2u(t)
return to Magnitude and Phase Spectra page