Response of an LTI system to a periodic input'

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Lecture 14

• Response of an LTI system to a periodic input.
• Application to rectifier example.
• Mean square approximation.
• Convergence in mean square.

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Response of an LTI system to a periodic input.
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Multiply magnitudes, add phases.
Attenuate higher frequencies lowpass filter.
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Back to rectifier example
DC
AC

yx
Idea add a lowpass filter in cascade to
attenuate the AC components, and get a
purer DC source.
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Rectifier plus filter


yx
H(s)
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What does z(t) look like?
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Mean square approximation
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Extension to Fourier
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Example Square Wave
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Example Square Wave
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Convergence in mean square
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Mean square convergence for the square wave