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Upsampling with en emphasis on the frequency domain  
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Upsampling with an emphasis on the frequency domain  
 
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</center> <font size="2">
By: Michael Deufel  
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By: Michael Deufel </font>
  
 
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<font size="4">1. Introduction</font>
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<font size="4">
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#Introduction  
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#Derivation
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#Examples
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#Conclusion
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</font>
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----
  
<font size="4">2. Derivation</font>
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<font size = 4>1. Introduction</font>
  
<font size="4">3. Examples</font>
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<font size = 3>The purpose of Upsampling is to manipulate a signal in order to artificially increase the sampling rate. This is done by...
  
<font size="4">4. Conclusion</font>
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#Discretize the signal
<font size="4">
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#Pad original signal with zeros
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#Take the DTFT
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#Send through a LPF (low pass filter)
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#Take the inverse DTFT to return to the time domain
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We will overview the whole process but focus on the effect upsampling has in the frequency domain</font>
 
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<font size="4">2. Derivation</font>
  
1. Introduction <font size="3"></font>
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<font size = 3>
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We will start with discrete signal  <math>x_1[n]</math>
  
<font size="3">The purpose of Upsampling is to manipulate a signal in order to increase the sampling rate.</font>
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now we "pad with zeros" to define <math>x_2[n]</math>
  
<font size="3">&nbsp; &nbsp; &nbsp;This is done by:</font>
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<math>x_2[n] = \begin{cases}x[\frac{n}{D}], & \text{if} \frac{n}{D} \in \mathbb{Z} \\0, &\text{else} \end{cases} f</math>
  
<font size="3"></font>&nbsp; &nbsp; &nbsp; &nbsp; Step 1: Descretise the signal&nbsp;
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<math>x_2[n]</math> can also be defined by
  
<font size="3">&nbsp; &nbsp; &nbsp; &nbsp; &nbsp;Step 1: Pad original signal with zeros</font>
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<math>x_2[n] = \sum_{n = -\inf}^{\inf} </math>
  
<font size="3">&nbsp; &nbsp; &nbsp; &nbsp; &nbsp;Step 2: Taking the DTFT</font>
 
  
<font size="3">&nbsp; &nbsp; &nbsp; &nbsp; &nbsp;Step 3: Sending through a LPF (low pass filter)</font>
 
  
<font size="3">&nbsp; &nbsp; &nbsp; &nbsp; &nbsp;Step 4:Taking the inverse DTFT to return to the time domain</font>
 
</font></font></font>
 
  
<font size="5"><font size="2"><font size="4"><font size="3">We will overview the whole process but focus on the effect upsampling has in the frequency domain </font> </font> </font> </font>
 
  
 
[[Category:Slecture]] [[Category:ECE438Fall2014Boutin]] [[Category:ECE]] [[Category:ECE438]] [[Category:Frequency_Upsampling]]
 
[[Category:Slecture]] [[Category:ECE438Fall2014Boutin]] [[Category:ECE]] [[Category:ECE438]] [[Category:Frequency_Upsampling]]

Revision as of 14:33, 14 October 2014


Upsampling with an emphasis on the frequency domain

By: Michael Deufel


  1. Introduction
  2. Derivation
  3. Examples
  4. Conclusion


1. Introduction

The purpose of Upsampling is to manipulate a signal in order to artificially increase the sampling rate. This is done by...

  1. Discretize the signal
  2. Pad original signal with zeros
  3. Take the DTFT
  4. Send through a LPF (low pass filter)
  5. Take the inverse DTFT to return to the time domain

We will overview the whole process but focus on the effect upsampling has in the frequency domain


2. Derivation

We will start with discrete signal $ x_1[n] $

now we "pad with zeros" to define $ x_2[n] $

$ x_2[n] = \begin{cases}x[\frac{n}{D}], & \text{if} \frac{n}{D} \in \mathbb{Z} \\0, &\text{else} \end{cases} f $

$ x_2[n] $ can also be defined by

$ x_2[n] = \sum_{n = -\inf}^{\inf} $

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