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I moved all content to the page itself instead of its discussion page. See [[Student_summary_CT_DT_Fourier_transform_ECE438F09|here]].--[[User:Mboutin|Mboutin]] 20:11, 1 September 2009 (UTC)
CTFT ( Continuous Time Fourier Transform )
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Equations**
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*<math>X(w) = \int{x(t)*exp(-jwt) dt }</math>
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*<math>x(t) = (1/2pi)\int{X(w)*exp(jwt) dw }</math>
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Duality Property
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* <math>'''{x(t)-CTFT->X(f)}'''</math>
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* <math>'''{X(t)-CTFT->x(-f)}'''</math>
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Example
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*<math>delta(t-t0) ->CTFT-> exp(-j2pi.f.t0)</math>
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*<math>exp(j.2pi.f0t) -> CTFT -> delta(f-f0)</math>
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Another Example:
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*<math>rect(t) -> CTFT -> sinc(f)</math>
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*<math>sinc(t) -> CTFT -> (rect(-f) = rect(f))</math>
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Cosine and Sine Functions
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*<math>cos(t) = 0.5 . ( delta(f - f0) + delta(f + f0) )</math>
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*<math>sin(t) = 0.5 i .( delta(f + f0) - delta(f - f0))</math>
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Rept and Comb Functions
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* <math>Rept(x(t)) = x(t) * sum(delta(t-kT))</math>
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*<math>Comb(x(t)) = x(t) . sum(delta(t-kT))</math>
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----------------------------------------
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DTFT ( Discrete Time Fourier Transform )
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* <math>X(w) = \sum{x(n)*exp(-jwn) dn }</math>
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* <math>x(t) = (1/2pi)\int{X(w)*exp(jwt) dw }</math>
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* Note that x[n] is always periodic with 2pi
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I will add more later.
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Latest revision as of 16:11, 1 September 2009

I moved all content to the page itself instead of its discussion page. See here.--Mboutin 20:11, 1 September 2009 (UTC)

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