(New page: Here we see that when the system input is <math> X_k[n]=\delta[n-k]\,</math> we get the following system output <math> Y_k[n]=(k+1)^2 \delta[n-(k+1)] \,</math> Hence if the input is ...)
 
 
(3 intermediate revisions by the same user not shown)
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== A) ==
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Here we see that when the system input is <math> X_k[n]=\delta[n-k]\,</math>     
 
Here we see that when the system input is <math> X_k[n]=\delta[n-k]\,</math>     
 
we get the following system output
 
we get the following system output
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Hence if the input is  
 
Hence if the input is  
 
*<math> X_k[n-n0]=\delta[n-n0-k]\,</math>  then the output shall be as follows  
 
*<math> X_k[n-n0]=\delta[n-n0-k]\,</math>  then the output shall be as follows  
*<math> Y_k[n-n0]=(k+1)^2 \delta[n-n0-(k+1)] \,</math>
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*<math> Y_k[x[n-n0]]=(k+1)^2 \delta[n-n0-(k+1)] \,</math>......................................(1)
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Now suppose we pass the signal through the system first and then delay it
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Therefore for input <math> X_k[n]=\delta[n-k]\,</math> we get
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<math> Y_k[n]=(k+1)^2 \delta[n-(k+1)] \,</math>
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Now, we delay Y_k[n] by n0
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*Therefore the output will be <math> Y_k[n-n0]=(k+1)^2 \delta[n-n0-(k+1)] \,</math>..............(2)
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'''From (1) and (2) it is clear that it is time invariant.'''
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== B) ==
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The input '''<math>u[n]</math>''' would yield '''<math>u[n-1]</math>'''

Latest revision as of 13:12, 12 September 2008

A)

Here we see that when the system input is $ X_k[n]=\delta[n-k]\, $ we get the following system output $ Y_k[n]=(k+1)^2 \delta[n-(k+1)] \, $

Hence if the input is

  • $ X_k[n-n0]=\delta[n-n0-k]\, $ then the output shall be as follows
  • $ Y_k[x[n-n0]]=(k+1)^2 \delta[n-n0-(k+1)] \, $......................................(1)

Now suppose we pass the signal through the system first and then delay it Therefore for input $ X_k[n]=\delta[n-k]\, $ we get $ Y_k[n]=(k+1)^2 \delta[n-(k+1)] \, $

Now, we delay Y_k[n] by n0

  • Therefore the output will be $ Y_k[n-n0]=(k+1)^2 \delta[n-n0-(k+1)] \, $..............(2)

From (1) and (2) it is clear that it is time invariant.


B)

The input $ u[n] $ would yield $ u[n-1] $

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