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[[Category:problem solving]]
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[[Category:ECE301]]
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[[Category:ECE]]
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[[Category:Fourier transform]]
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[[Category:signals and systems]]
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== Example of Computation of Fourier transform of a CT SIGNAL ==
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A [[CT_Fourier_transform_practice_problems_list|practice problem on CT Fourier transform]]
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Compute the Fourier Transform of x(t):
 
Compute the Fourier Transform of x(t):
  
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=\frac{2}{3+j\omega}+\frac{8sin(3\omega)}{\omega}
 
=\frac{2}{3+j\omega}+\frac{8sin(3\omega)}{\omega}
 
</math>
 
</math>
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----
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[[CT_Fourier_transform_practice_problems_list|Back to Practice Problems on CT Fourier transform]]

Latest revision as of 11:35, 16 September 2013

Example of Computation of Fourier transform of a CT SIGNAL

A practice problem on CT Fourier transform


Compute the Fourier Transform of x(t):

$ \,x(t)=2e^{-3t}u(t)+4[u(t+3)-u(t-3)] $

Using the Formula for Fourier Transforms:

$ \mathcal{F}(x(t))= \mathcal{X}(\omega)= \int_{-\infty}^{\infty}x(t)e^{-j\omega t} \,dt $

So the calculation follows as:

$ \mathcal{X}(\omega)= \int_{-\infty}^{\infty}(2e^{-3t}u(t)+4[u(t+3)-u(t-3)])e^{-j\omega t} \,dt $

$ =2\int_{0}^{\infty}e^{-t(3+j\omega)}\,dt + 4\int_{-3}^{3}e^{-j\omega t}\, dt $

$ =2\frac{-e^{-t}}{3+j\omega}\bigg|^{\infty}_{0}+4\frac{-e^{-j\omega t}}{j\omega}\bigg|^{3}_{-3} $

$ =2\frac{1}{3+j\omega}+4*\frac{2}{\omega}*\frac{-e^{-3j\omega} + e^{3j\omega}}{2j} $ and using eulers identity for sin:

$ =\frac{2}{3+j\omega}+\frac{8sin(3\omega)}{\omega} $


Back to Practice Problems on CT Fourier transform

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