(Linearity and Time Invariance)
(Time Invariant System?)
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=Time Invariant System?=
 
=Time Invariant System?=
 
Suppose the system is defined as the third line where input is <math>X_2[n]=&delta;[n-2]</math> and output: <math>Y_2[n]=9 &delta;[n-3]</math> with a time delay of .  Using the same method as in Part D, we can determine whether this system is time invariant or not.
 
Suppose the system is defined as the third line where input is <math>X_2[n]=&delta;[n-2]</math> and output: <math>Y_2[n]=9 &delta;[n-3]</math> with a time delay of .  Using the same method as in Part D, we can determine whether this system is time invariant or not.
 
&delta;[n] -> time delay -> &delta;[n-3] -> system -> 16&delta;[n-4]
 
 
&delta;[n] -> system -> &delta;[n-1] -> time delay -> &delta;[n-4]
 
 
 
Since both cascades produce different outputs, this system is NON-time invariant.
 

Revision as of 10:57, 12 September 2008

Linearity and Time Invariance

Given system:

Input Output

X0[n]=δ[n] -> Y0[n]=δ[n-1]

X1[n]=δ[n-1] -> Y1[n]=4δ[n-2]

X2[n]=δ[n-2] -> Y2[n]=9 δ[n-3]

X3[n]=δ[n-3] -> Y3[n]=16 δ[n-4]

... -> ...

Xk[n]=δ[n-k] -> Yk[n]=(k+1)2 δ[n-(k+1)] -> For any non-negative integer k


Time Invariant System?

Suppose the system is defined as the third line where input is $ X_2[n]=&delta;[n-2] $ and output: $ Y_2[n]=9 &delta;[n-3] $ with a time delay of . Using the same method as in Part D, we can determine whether this system is time invariant or not.

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