(New page: {| | align="left" style="padding-left: 0em;" | CTFT of a sinc |- | <math> X(f)=\mathcal{X}(2\pi f)=\left\{\begin{array}{ll}1, & \text{ if }|f| <\frac{W}{2\pi},\\ 0, & \text{else.}\end{a...)
 
 
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=How to obtain the CTFT of a sinc in terms of f in hertz (from the formula in terms of <math>\omega</math>) =
| align="left" style="padding-left: 0em;" | CTFT of a sinc  
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Recall:
| <math> X(f)=\mathcal{X}(2\pi f)=\left\{\begin{array}{ll}1, &  \text{ if }|f| <\frac{W}{2\pi},\\ 0, & \text{else.}\end{array} \right.  \ </math>
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<math>x(t)=\frac{2 \sin \left( W t  \right)}{\pi t }</math>
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<math>\mathcal{X}(\omega)=\left\{\begin{array}{ll}1, &  \text{ if }|\omega| <W,\\ 0, & \text{else.}\end{array} \right.</math>
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To obtain X(f), use the substitution
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<math>\omega= 2 \pi f </math>.
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More specifically
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<math> X(f)=\mathcal{X}(2\pi f)=\left\{\begin{array}{ll}1, &  \text{ if }|f| <\frac{W}{2\pi},\\ 0, & \text{else.}\end{array} \right.  \ </math>
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[[ECE438_HW1_Solution|Back to Table]]

Latest revision as of 11:59, 15 September 2010

How to obtain the CTFT of a sinc in terms of f in hertz (from the formula in terms of $ \omega $)

Recall:

$ x(t)=\frac{2 \sin \left( W t \right)}{\pi t } $

$ \mathcal{X}(\omega)=\left\{\begin{array}{ll}1, & \text{ if }|\omega| <W,\\ 0, & \text{else.}\end{array} \right. $

To obtain X(f), use the substitution

$ \omega= 2 \pi f $.

More specifically

$ X(f)=\mathcal{X}(2\pi f)=\left\{\begin{array}{ll}1, & \text{ if }|f| <\frac{W}{2\pi},\\ 0, & \text{else.}\end{array} \right. \ $


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