(CT Fourier Transform)
 
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*[[Table of Formulas and Properties_ECE301Fall2008mboutin#DT Fourier Transform Properties|DT Fourier Transform Properties]]
 
*[[Table of Formulas and Properties_ECE301Fall2008mboutin#DT Fourier Transform Properties|DT Fourier Transform Properties]]
  
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== Frequency Response ==
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Frequency response in CT and DT are very similar. They both have the form of <math>\ Y(\omega) = H(\omega)X(\omega)</math>. This form is obtained through differential equations in CT and difference equations in DT.
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Here is a CT example we did in class:
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<math>\frac{d}{dt}y(t) + 4y(t) = x(t)</math>
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Taking the Fourier transform of both sides yields <math>\ j\omega Y(\omega) + 4Y(\omega) = \mathcal{X}(\omega)</math>.
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Solving for <math>Y(\omega)</math> gives us <math>Y(\omega) = \frac{1}{j\omega +4}\mathcal{X}(\omega)</math>. From this <math>H(\omega)</math> can be observed as <math>\frac{1}{j\omega +4}</math>.
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By taking the Fourier inverse of <math>\ H(\omega)</math> the unit impulse response can be found.
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<math>\ h(t)</math>in this problem can be found from looking at the table of CT FT Pairs, so <math>\ h(t) = e^{-4t}u(t)</math>
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Latest revision as of 16:12, 24 October 2008

CT Fourier Transform

DT Fourier Transform

Frequency Response

Frequency response in CT and DT are very similar. They both have the form of $ \ Y(\omega) = H(\omega)X(\omega) $. This form is obtained through differential equations in CT and difference equations in DT.

Here is a CT example we did in class:

$ \frac{d}{dt}y(t) + 4y(t) = x(t) $ Taking the Fourier transform of both sides yields $ \ j\omega Y(\omega) + 4Y(\omega) = \mathcal{X}(\omega) $.

Solving for $ Y(\omega) $ gives us $ Y(\omega) = \frac{1}{j\omega +4}\mathcal{X}(\omega) $. From this $ H(\omega) $ can be observed as $ \frac{1}{j\omega +4} $.

By taking the Fourier inverse of $ \ H(\omega) $ the unit impulse response can be found.

$ \ h(t) $in this problem can be found from looking at the table of CT FT Pairs, so $ \ h(t) = e^{-4t}u(t) $


This entry contains some previously defined entries. They are placed all on this page in order save time navigation wise.

Alumni Liaison

has a message for current ECE438 students.

Sean Hu, ECE PhD 2009