(Periodic CT Signal)
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<math>x(t) = \frac{e^{14jt}}{2j}-\frac{e^{-14jt}}{2j} + \frac{(1+3j)*e^{2jt}}{2} + \frac{(1+3j)e^{-2jt}}{2}</math>
 
<math>x(t) = \frac{e^{14jt}}{2j}-\frac{e^{-14jt}}{2j} + \frac{(1+3j)*e^{2jt}}{2} + \frac{(1+3j)e^{-2jt}}{2}</math>
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I contend that the <math>\omega_0=2</math> since both functions are periodic based on it.
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<math>a_7=\frac{1}{2j}</math>
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<math> a_{-7} = \frac{-1}{2j}</math>
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<math> a_1 = \frac{1+3j}{2} </math>
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<math> a_{-1} = \frac{1+3j}{2} </math>
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We can write this as a sum:
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<math> x(t)=\sum^{\infty}_{k = -\infty} a_k  e^{j2k}\,</math>
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Where
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<math> a_1=a_{-1}=\frac{1+3j}{2} </math>
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<math> a_7 = -a_{-7} = \frac{1}{2j} </math>
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<math> a_k = 0, k \= 1, -1, 7, -7 </math>

Revision as of 15:19, 25 September 2008

Periodic CT Signal

The first signal that comes to mind when i think of a periodic CT signal is one involving sines and cosines, so let's work with one of those.

Let $ x(t) = sin(14t)+(1+3j)cos(2t) $

This can also be expressed as

$ x(t) = \frac{e^{14jt}}{2j}-\frac{e^{-14jt}}{2j} + \frac{(1+3j)*e^{2jt}}{2} + \frac{(1+3j)e^{-2jt}}{2} $

I contend that the $ \omega_0=2 $ since both functions are periodic based on it.

$ a_7=\frac{1}{2j} $

$ a_{-7} = \frac{-1}{2j} $

$ a_1 = \frac{1+3j}{2} $

$ a_{-1} = \frac{1+3j}{2} $

We can write this as a sum:

$ x(t)=\sum^{\infty}_{k = -\infty} a_k e^{j2k}\, $

Where

$ a_1=a_{-1}=\frac{1+3j}{2} $

$ a_7 = -a_{-7} = \frac{1}{2j} $

$ a_k = 0, k \= 1, -1, 7, -7 $

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