Spectrum Limitations
September 30th, 2022
(See attached file for full problem description)
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A signal x(t) of finite energy is applied to a square-law device whose output y(t) is given by
y(t) = x2(t)
The spectrum of x(t) is limited to the frequency interval -W ≤ f ≤ W. Show that the spectrum of y(t) is limited to -2W ≤ f ≤ 2W.
(Hint: Express y(t) as x(t) multiplied by itself.)
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