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==Definition==
 
The easiest way to think of time invariance is to use the vertical and horizontal line test.  x(t) is the horizontal axis and y(t) is the vertical axis.
 
The easiest way to think of time invariance is to use the vertical and horizontal line test.  x(t) is the horizontal axis and y(t) is the vertical axis.
  
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[[Image:vertical_ECE301Fall2008mboutin.jpg]]
 
[[Image:vertical_ECE301Fall2008mboutin.jpg]]
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[[Image:horizontal_ECE301Fall2008mboutin.jpg]]
 
[[Image:horizontal_ECE301Fall2008mboutin.jpg]]
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==Time Invariant System==
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<math>y=exp(x)</math>
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This function passes both the horizontal and vertical line tests.
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[[Image:TI_ECE301Fall2008mboutin.jpg]]
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==Non-Time Invariant System==
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<math>y=x^2</math>
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This function fails the horizontal line test.
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[[Image:NonTI_ECE301Fall2008mboutin.jpg]]

Latest revision as of 13:25, 10 September 2008

Definition

The easiest way to think of time invariance is to use the vertical and horizontal line test. x(t) is the horizontal axis and y(t) is the vertical axis.

x(t) --> system 1 --> y(t)

Vertical ECE301Fall2008mboutin.jpg

Horizontal ECE301Fall2008mboutin.jpg

Time Invariant System

$ y=exp(x) $ This function passes both the horizontal and vertical line tests. TI ECE301Fall2008mboutin.jpg

Non-Time Invariant System

$ y=x^2 $ This function fails the horizontal line test. NonTI ECE301Fall2008mboutin.jpg

Alumni Liaison

Correspondence Chess Grandmaster and Purdue Alumni

Prof. Dan Fleetwood