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In order to get rid of aliasing, what is the cut-off frequency of the low pass filter? Explain your answer.  
 
In order to get rid of aliasing, what is the cut-off frequency of the low pass filter? Explain your answer.  
 
Answer [[ECE438_Week6_Quiz_Q2sol|here]].
 
Answer [[ECE438_Week6_Quiz_Q2sol|here]].
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----
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The following two systems are used to process a signal
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[[Image:ECE438SystemSampling.jpg]]
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Assume that the input signal X(f) and the continuous time filter H(f) are both band limited to 1/(2T).
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3. <math>\text{Compute expressions for Y} (e^{j\omega})\text{ and H}(e^{j\omega})</math>.
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4. Show that when
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<math>G(e^{j\omega}) = \sum_{n=-\infty}^{\infty} H \Bigg( \frac{\omega - 2k\pi}{2k\pi}\Bigg)</math>
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then the output of the two systems is equal.
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Answer [[ECE438_Week6_Quiz_Q3_Q4sol|here]].
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[[ECE438_Lab_Fall_2010|Back to Lab Wiki]]
 
[[ECE438_Lab_Fall_2010|Back to Lab Wiki]]

Revision as of 04:45, 27 September 2010

$ \text{ Sample a continuous signal x(t)=sin(}\omega t)\text{ with period of T, } $

1) In order to avoid aliasing, what is the maximum value of T? Write down the discrete time signal x(n) with the maximum T. Answer here.

2) The system diagram is as follows.

Sys diagram.jpg

In order to get rid of aliasing, what is the cut-off frequency of the low pass filter? Explain your answer. Answer here.


The following two systems are used to process a signal

ECE438SystemSampling.jpg

Assume that the input signal X(f) and the continuous time filter H(f) are both band limited to 1/(2T).

3. $ \text{Compute expressions for Y} (e^{j\omega})\text{ and H}(e^{j\omega}) $.

4. Show that when

$ G(e^{j\omega}) = \sum_{n=-\infty}^{\infty} H \Bigg( \frac{\omega - 2k\pi}{2k\pi}\Bigg) $

then the output of the two systems is equal.

Answer here.




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