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*Under construction --[[User:zhao148|Zhao]]
 
*Under construction --[[User:zhao148|Zhao]]
 
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Q1.  
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Q1. Consider the discrete-time signal
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<math>x[n]=2\delta[n]+5 \delta[n-1]+\delta[n-1]- \delta[n-2].</math>
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a) Determine the DTFT <math>X(\omega)</math> of x[n] and the DTFT of <math>Y(\omega)</math> of y[n]=x[-n].
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 +
b) Using your result from part a), compute
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<math>x[n]* y[n]</math>.
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c) Consider the discrete-time signal
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<math>z[n]=\left\{ \begin{array}{ll}x[(-n)\mod 4],& 0\leq n < 3,\\ 0 & \text{else }\end{array} \right. </math>. 
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Obtain the 4-point circular convolution of x[n] and z[n].
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d) When computing the N-point circular convolution of x[n] and the signal
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<math>z[n]=\left\{ \begin{array}{ll}x[(-n)\mod N],& 0\leq n < N-1,\\ 0 & \text{else }\end{array} \right. </math>. 
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how should N be chosen to make sure that the result is the same as the usual convolution between x[n] and z[n]? 
  
 
* Same as HW8 Q3 available [[ECE438_HW8_Solution|here]].
 
* Same as HW8 Q3 available [[ECE438_HW8_Solution|here]].

Revision as of 13:36, 16 November 2010


Quiz Questions Pool for Week 13

  • Under construction --Zhao

Q1. Consider the discrete-time signal

$ x[n]=2\delta[n]+5 \delta[n-1]+\delta[n-1]- \delta[n-2]. $

a) Determine the DTFT $ X(\omega) $ of x[n] and the DTFT of $ Y(\omega) $ of y[n]=x[-n].

b) Using your result from part a), compute

$ x[n]* y[n] $.

c) Consider the discrete-time signal

$ z[n]=\left\{ \begin{array}{ll}x[(-n)\mod 4],& 0\leq n < 3,\\ 0 & \text{else }\end{array} \right. $.

Obtain the 4-point circular convolution of x[n] and z[n].

d) When computing the N-point circular convolution of x[n] and the signal

$ z[n]=\left\{ \begin{array}{ll}x[(-n)\mod N],& 0\leq n < N-1,\\ 0 & \text{else }\end{array} \right. $.

how should N be chosen to make sure that the result is the same as the usual convolution between x[n] and z[n]?

  • Same as HW8 Q3 available here.

Q2.


Q3.


Q4.


Q5.


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