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'''''Conjugation Property'''
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'''''Conjugation Property and Conjugate Symmetry'''
  
 
  The conjugation property states that  if the <math>\mathcal{F}</math> of x(t) will be equal to X(jw)  
 
  The conjugation property states that  if the <math>\mathcal{F}</math> of x(t) will be equal to X(jw)  
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   <math>X^* (jw)=[\int\limits_{-\infty}^{\infty}x(t)e^{(-\jmath wt)}dt]^*</math>  
 
   <math>X^* (jw)=[\int\limits_{-\infty}^{\infty}x(t)e^{(-\jmath wt)}dt]^*</math>  
 
            
 
            
   <math>X^* (jw)=\int\limits_{-\infty}^{\infty}x(t)e^{(-\jmath wt)}dt
+
   <math>X^* (jw)=\int\limits_{-\infty}^{\infty}x^* (t)e^{(\jmath wt)}dt</math>
 +
 +
Replacing w with -w, 
 +
  <math>X^* (-jw)=\int\limits_{-\infty}^{\infty}x^* (t)e^{(-\jmath wt)}dt</math>
 +
  (The right hand side of this equation is the Fourier transform analysis equation for x*(t))
 +
 +
The conjugation property shows that if x(t) is real, then X(jw) has conjugate symmetry
 +
  <math> X(-\jmath w) = X^* (\jmath w)</math>
 +
where [x(t) real]

Latest revision as of 04:37, 9 July 2009

Conjugation Property and Conjugate Symmetry

The conjugation property states that  if the $ \mathcal{F} $ of x(t) will be equal to X(jw) 
then,
the $ \mathcal{F} $ of x*(t) will be equal to X*(-jw)

This property follows from the evaluation of the complex conjugate of
 $ X^* (jw)=[\int\limits_{-\infty}^{\infty}x(t)e^{(-\jmath wt)}dt]^* $ 
         
 $ X^* (jw)=\int\limits_{-\infty}^{\infty}x^* (t)e^{(\jmath wt)}dt $

Replacing w with -w,  
 $ X^* (-jw)=\int\limits_{-\infty}^{\infty}x^* (t)e^{(-\jmath wt)}dt $ 
  (The right hand side of this equation is the Fourier transform analysis equation for x*(t)) 

The conjugation property shows that if x(t) is real, then X(jw) has conjugate symmetry 
 $  X(-\jmath w) = X^* (\jmath w) $ 
where [x(t) real]

Alumni Liaison

Ph.D. 2007, working on developing cool imaging technologies for digital cameras, camera phones, and video surveillance cameras.

Buyue Zhang