1. Net 222: Communications and networks fundamentals (Practical Part)
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Lab 5 : linear and Time invariance system

2. Lecture Contants Linear system Time invariance system
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3. Linear System
If a system is linear, this means that when an input to a given system is scaled by a value, the output of the system is scaled by the same amount.
Ya[n]=Yb[n] is linear system.

4. Linear system coding
We could write a system that test if the giving input are linear or NOT
Eg: yn[n]=x[n]^4
By Assuming :
X[n]1=sin(3)
X[n]2=sin(5)
Scaling value a=4
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5. Example
output
YA != YB
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6. Example Another Eg: yn[n]= 2*x[n] YA = YB X[n]1=sin(3) X[n]2=sin(5)
Scaling value a=4
output
YA = YB
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7. Time-Invariant System :
X[n]
Y1[n]=y[n-n0] S T
Y2[n]=T{x[n-n0]}
Y1[n]=Y2[n] for all n
T is time invariant
24-Feb-19
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8. Example
We could write a system that test if the giving input are linear or NOT
Eg: yn[n]=x[n]*sin(3)
By Assuming :
X[n]=3
Shifting value n0=4
output
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9. The End
Any Questions ?
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