(New page: Category:slecture Category:ECE438Fall2014Boutin Category:ECE Category:ECE438 Category:signal processing <center><font size= 5> Inverse Z Transform </font size></cen...)
 
(This is a page dedicated the working out inverse z transforms by direct inversion)
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<math>x[n]=\mathcal{L}^{-1}(X(z))=\frac{1}{2\pi j}\oint_{c}X(z)z^{n-1}dz</math>
 
<math>x[n]=\mathcal{L}^{-1}(X(z))=\frac{1}{2\pi j}\oint_{c}X(z)z^{n-1}dz</math>
 
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1. Example Problems of the Inverse Z Transform
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:We will find the Inverse Z transform of various signals by manipulation and then using direct Inversion
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Ex. 1 Find the Inverse Z transform of the following signal
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<math>X(z)=\frac{1}{1-z}, \text{ ROC } |z|<1 </math>
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:<font size = 2>note: It is important to realize that we are not going to try to use the direct formula for an inverse Z transform, Instead our approach will be to manipulate the signal so that we can directly compare it with the Z transform equation and by inspection obtain the Inverse Z transform.</font size>
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<font size= 2>First we need to manipulate the given ROC equation to be in the following form, with 'A' being some expression that contains z</font size>
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<center><math>|A| < 1</math></center>

Revision as of 14:50, 13 December 2014


Inverse Z Transform

Overview

The purpose of this page is to...
1. Define the Z Transform and Inverse Z Transform
2. Provide Example Problems of the Inverse Z Transform

1. Definitions

Z Transform

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

Inverse Z Transform

$ x[n]=\mathcal{L}^{-1}(X(z))=\frac{1}{2\pi j}\oint_{c}X(z)z^{n-1}dz $

1. Example Problems of the Inverse Z Transform

We will find the Inverse Z transform of various signals by manipulation and then using direct Inversion

Ex. 1 Find the Inverse Z transform of the following signal

$ X(z)=\frac{1}{1-z}, \text{ ROC } |z|<1 $

note: It is important to realize that we are not going to try to use the direct formula for an inverse Z transform, Instead our approach will be to manipulate the signal so that we can directly compare it with the Z transform equation and by inspection obtain the Inverse Z transform.

First we need to manipulate the given ROC equation to be in the following form, with 'A' being some expression that contains z

$ |A| < 1 $

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