(Linearity)
(Linearity)
Line 12: Line 12:
 
  x1[n] + x2[n] = xtot[n] = <math>2n + n^2</math> ====> ytot[n] = 4* xtot[n] = <math>8n + 4n^2</math>
 
  x1[n] + x2[n] = xtot[n] = <math>2n + n^2</math> ====> ytot[n] = 4* xtot[n] = <math>8n + 4n^2</math>
  
  x1[n] ==> y1[n] = 8n               x2[n] ==> y2[n] = <math>4n^2</math>  ====>    ytot = y1[n] + y2[n] = <math>8n + 4n^2</math>   
+
  x1[n] => y1[n] = 8n       x2[n] => y2[n] = <math>4n^2</math>  ====>    ytot = y1[n] + y2[n] = <math>8n + 4n^2</math>   
  
 
  <math>8n + 4n^2</math>  =    <math>8n + 4n^2</math>
 
  <math>8n + 4n^2</math>  =    <math>8n + 4n^2</math>
  
 
  Since the output of the two are the same, the system is linear.
 
  Since the output of the two are the same, the system is linear.

Revision as of 09:02, 11 September 2008

Linearity

Linearity- A system is linear if a constant that multiplies an input to a system is also present in the output. Adding any number of linear combinations of complex numbers and functions of time together does not affect the linearity of the system.

A*x1(t) + B*x2(t) => A*y1(t) + B*y2(t) .... extendable for any amount of complex numbers (A, B, C...) and functions (x1, x2, x3...)

Linear System:  y[n] = 4 * x[n]
Let x1[n] = $ 2n $ 
    x2[n] = $ n^2 $

x1[n] + x2[n] = xtot[n] = $ 2n + n^2 $ ====> ytot[n] = 4* xtot[n] = $ 8n + 4n^2 $
x1[n] => y1[n] = 8n        x2[n] => y2[n] = $ 4n^2 $  ====>     ytot = y1[n] + y2[n] = $ 8n + 4n^2 $   
$ 8n + 4n^2 $   =    $ 8n + 4n^2 $
Since the output of the two are the same, the system is linear.

Alumni Liaison

Ph.D. on Applied Mathematics in Aug 2007. Involved on applications of image super-resolution to electron microscopy

Francisco Blanco-Silva