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= Practice Question on sampling and reconstruction (related to Nyquist rate)  =
 
= Practice Question on sampling and reconstruction (related to Nyquist rate)  =
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The signal  
 
The signal  
  
 
<math> x(t)= e^{j \frac{\pi}{2} t }\frac{\sin (6 \pi t)}{  t} </math>  
 
<math> x(t)= e^{j \frac{\pi}{2} t }\frac{\sin (6 \pi t)}{  t} </math>  
  
is sampled with a sampling period <math class="inline"> T</math>. For what values of T is it possible to reconstruct the signal from its sampling?
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is sampled with a sampling period <span class="texhtml">''T''</span>. For what values of T is it possible to reconstruct the signal from its sampling?  
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== Share your answers below  ==
 
== Share your answers below  ==
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You will receive feedback from your instructor and TA directly on this page. Other students are welcome to comment/discuss/point out mistakes/ask questions too!  
 
You will receive feedback from your instructor and TA directly on this page. Other students are welcome to comment/discuss/point out mistakes/ask questions too!  
  
 
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=== Answer 1  ===
 
=== Answer 1  ===
Using the table and a time shift
 
  
&nbsp;X(w) = pi[u(w+6pi-pi/2) - u(w-6pi-pi/2)]
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Using the table and a time shift
  
&nbsp;&nbsp; &nbsp; &nbsp; &nbsp;= pi[u(w+11pi/2) - u(w-13pi/2)]
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&nbsp;X(w) = pi[u(w+6pi-pi/2) - u(w-6pi-pi/2)]  
  
<br>
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&nbsp;&nbsp; &nbsp; &nbsp; &nbsp;= pi[u(w+11pi/2) - u(w-13pi/2)]
  
Thus the signal is band limited wm = 13pi/2, so ws &gt; Nyquist Rate = 2wm = 13pi
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<br>
  
Since T = 2pi/ws
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Thus the signal is band limited wm = 13pi/2, so ws &gt; Nyquist Rate = 2wm = 13pi
  
T &lt; 2pi/13pi = 2/13
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Since T = 2pi/ws
  
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T &lt; 2pi/13pi = 2/13
  
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<br>
  
T &lt; 2/13 in order to recover the orginal signal
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T &lt; 2/13 in order to recover the orginal signal  
--[[User:Ssanthak|Ssanthak]] 12:38, 21 April 2011 (UTC)
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--[[User:Ssanthak|Ssanthak]] 12:38, 21 April 2011 (UTC)  
  
 
=== Answer 2  ===
 
=== Answer 2  ===
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  Write it here
 
  Write it here
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=== Answer 3  ===
 
=== Answer 3  ===
Write it here.
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Write it here.  
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Revision as of 08:39, 21 April 2011

Practice Question on sampling and reconstruction (related to Nyquist rate)

The signal

$ x(t)= e^{j \frac{\pi}{2} t }\frac{\sin (6 \pi t)}{ t} $

is sampled with a sampling period T. For what values of T is it possible to reconstruct the signal from its sampling?


Share your answers below

You will receive feedback from your instructor and TA directly on this page. Other students are welcome to comment/discuss/point out mistakes/ask questions too!


Answer 1

Using the table and a time shift

 X(w) = pi[u(w+6pi-pi/2) - u(w-6pi-pi/2)]

        = pi[u(w+11pi/2) - u(w-13pi/2)]


Thus the signal is band limited wm = 13pi/2, so ws > Nyquist Rate = 2wm = 13pi

Since T = 2pi/ws

T < 2pi/13pi = 2/13


T < 2/13 in order to recover the orginal signal

--Ssanthak 12:38, 21 April 2011 (UTC)

Answer 2

Write it here

Answer 3

Write it here.


Back to ECE301 Spring 2011 Prof. Boutin

Alumni Liaison

Ph.D. 2007, working on developing cool imaging technologies for digital cameras, camera phones, and video surveillance cameras.

Buyue Zhang