1
EE214A Lecture 2
Abeer Alwan
Last Time
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Frequency Transforms for CT and DT signals:
Periodic signals have a line spectrum while
aperiodic signals have a continuous spectrum.
Also recall that:
frequency
sampling
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2
Why is the DTFT periodic?
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Hence
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Hence, the DTFT is periodic in
2
Today
•
Sampling Theorem
•
Decimation and Interpolation
•
LTI (or LSI) systems