(Periodic Signals Revisited)
(Part 2)
 
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Found here: http://cobweb.ecn.purdue.edu/~mboutin/ECE301/Index.html
 
Found here: http://cobweb.ecn.purdue.edu/~mboutin/ECE301/Index.html
  
[[Image:sin5t_ECE301Fall2008mboutin.png|200px|thumb|left]]
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I chose to modify the signal a bit and make it y = sin(5t).
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[[Image:sin5t_ECE301Fall2008mboutin.png]]
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:If you plot the signal in DT sampling at 5Hz you get a non-periodic signal as follows:
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[[Image:sin5tnonper_ECE301Fall2008mboutin.png]]
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:It looks very close to periodic, but it does not follow the definition of x(n+N) = x(n) that was learned in class.  However, there are no integer values that can be used to sample this function to create a periodic function in DT.
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:One can use <math> pi/3 </math> to sample the function and create a periodic signal.
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[[Image:sin5tper_ECE301Fall2008mboutin.png]]
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==Part 2==
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We can take a non-periodic signal <math> y(t) = exp(t) </math> and shift it an infinite number of times periodically to create a periodic signal.
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[[Image:PeriExp_ECE301Fall2008mboutin.png]]

Latest revision as of 09:22, 11 September 2008

Periodic Signals Revisited

The function chosen (by randomly clicking a name) from hw1 is y=sin(t). Found here: http://cobweb.ecn.purdue.edu/~mboutin/ECE301/Index.html

I chose to modify the signal a bit and make it y = sin(5t).

Sin5t ECE301Fall2008mboutin.png

If you plot the signal in DT sampling at 5Hz you get a non-periodic signal as follows:

Sin5tnonper ECE301Fall2008mboutin.png

It looks very close to periodic, but it does not follow the definition of x(n+N) = x(n) that was learned in class. However, there are no integer values that can be used to sample this function to create a periodic function in DT.
One can use $ pi/3 $ to sample the function and create a periodic signal.

Sin5tper ECE301Fall2008mboutin.png

Part 2

We can take a non-periodic signal $ y(t) = exp(t) $ and shift it an infinite number of times periodically to create a periodic signal.

PeriExp ECE301Fall2008mboutin.png

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