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Therefore, <math>x[n + 2\pi] = x[n]</math>  
 
Therefore, <math>x[n + 2\pi] = x[n]</math>  
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For this discrete time signal which was produced by sampling the same sine wave at a frequency of 1, the values of x[n] are non-periodic because <math>x[n + k] \neq x[n]</math>
 
For this discrete time signal which was produced by sampling the same sine wave at a frequency of 1, the values of x[n] are non-periodic because <math>x[n + k] \neq x[n]</math>
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==2. Create a periodic signal by summing shifted copies of a non-periodic signal==

Revision as of 09:00, 11 September 2008

1. Creating two DT signals (one periodic and one non-periodic) from a periodic CT signal

Let x(t) = sin (t), which is a periodic CT signal

x(t) = sin (t) Sin1 ECE301Fall2008mboutin.jpg


Sampling every t = 0.01 Samp0 ECE301Fall2008mboutin.jpg


Periodic Signal

Sampling every $ t = \pi $ Samp pi ECE301Fall2008mboutin.jpg

This discrete time signal was produced from a CT sine wave by sampling at a frequency of $ \frac{1}{\pi} $.

As can be seen from the graph, the values of x[n] are periodic because they repeat after every period of $ t = 2\pi $.

Therefore, $ x[n + 2\pi] = x[n] $


Non Periodic Signal

Sampling every t = 1 Samp1 ECE301Fall2008mboutin.jpg

For this discrete time signal which was produced by sampling the same sine wave at a frequency of 1, the values of x[n] are non-periodic because $ x[n + k] \neq x[n] $


2. Create a periodic signal by summing shifted copies of a non-periodic signal

Alumni Liaison

Correspondence Chess Grandmaster and Purdue Alumni

Prof. Dan Fleetwood