(Computing the Inverse Z.T.)
(Computing the Inverse Z.T.)
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<b>Warning <math>|2z^{-1}| = \frac{2}{z} > 1</math>!!</b>
 
<b>Warning <math>|2z^{-1}| = \frac{2}{z} > 1</math>!!</b>
  
<math> = \frac{1}{1-\frac{2}{z}} = \frac{z}{z-2} = \frac{z}{-2({1-\frac{z}{2})}</math>
+
<math> = \frac{1}{1-\frac{2}{z}} = \frac{z}{z-2} = \frac{z}{-2(1-\frac{z}{2})}</math>

Revision as of 14:28, 30 November 2008

Z Transform

Discrete analog of Laplace Transform

$ X(z) = \sum_{n = -\infty}^\infty x[n]z^{-n} $

    Where z is a complex variable.

Relationship between Z-Transform and F.T.

$ X(\omega) = X(e^{j\omega}) $
$ X(z)=X(re^{j\omega}) $

Then $ X(z) = F(x[n]r^{-n}) $

$ X(z) = \sum_{n = -\infty}^\infty x[n]z^{-n} = \sum_{n = -\infty}^\infty x[n](re^{j\omega})^{-n} = \sum_{n = -\infty}^\infty x[n]r^{-n}e^{-j\omega n} $

Where $ \sum_{n = -\infty}^\infty x[n]r^{-n}e^{-j\omega n} $ is the F.T!

Properties of the ROC

Refer to Xujun Huang: Properties of ROC_ECE301Fall2008mboutin

Computing the Inverse Z.T.

$ X(z) = \frac{1}{1-2z^{-1}} , |z| < 2 $

Warning $ |2z^{-1}| = \frac{2}{z} > 1 $!!

$ = \frac{1}{1-\frac{2}{z}} = \frac{z}{z-2} = \frac{z}{-2(1-\frac{z}{2})} $

Alumni Liaison

Recent Math PhD now doing a post-doctorate at UC Riverside.

Kuei-Nuan Lin