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= '''1. Introduction'''  =
 
= '''1. Introduction'''  =
  
=== <br> &nbsp; &nbsp; &nbsp;Sampling is essential to convert analog signal to digital signal. In this page, I would specifically<br> explain about downsampling. In digital signal processing, the decimator performs decimation, which is<br> downsampling a signal. In other words, when a digital signal is downsampled, the signal's sampling<br> rate would be reduced. <br>  ===
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===== &nbsp;&nbsp;&nbsp;&nbsp; Sampling is essential to convert analog signal to digital signal. In this page, I would specifically<br>explain about downsampling. In digital signal processing, the decimator performs decimation, which is<br>downsampling a signal. In other words, when a digital signal is downsampled, the signal's sampling<br>rate would be reduced. =====
  
= [[Image:Intro1.jpg]] =
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===== [[Image:Intro1.jpg]] =====
  
 
=  =
 
=  =
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= <br> '''2. Derivation'''  =
 
= <br> '''2. Derivation'''  =
  
<br> [[Image:Sdf21le.jpg]] <br> [[Image:Derivation2.jpg]] <br> [[Image:Derivaa3.jpg]]&nbsp;
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<br> [[Image:Sdf21le.jpg]] <br> [[Image:Derivation2.jpg]] <br> [[Image:Derivaa3.jpg]]&nbsp;  
  
 
=  =
 
=  =
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= <br> '''4. Conclusion'''  =
 
= <br> '''4. Conclusion'''  =
  
= <br> Downsampling reduces the magnitude by a factor of D, and increases the width of signals by D in the frequency domain.<br> Moreover, it repeats it's signals every 2π and to prevent aliasing, decimator needs a lowpass filter before the downsampling.
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===== <br>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Downsampling reduces the magnitude by a factor of D, and increases the width of signals by D in the frequency domain. Moreover, it repeats it's signals every 2π and to prevent aliasing, decimator needs a lowpass filter before the downsampling.  =====
  <br> =
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Revision as of 11:57, 10 October 2014

1. Introduction

     Sampling is essential to convert analog signal to digital signal. In this page, I would specifically
explain about downsampling. In digital signal processing, the decimator performs decimation, which is
downsampling a signal. In other words, when a digital signal is downsampled, the signal's sampling
rate would be reduced.
Intro1.jpg


2. Derivation


Sdf21le.jpg
Derivation2.jpg
Derivaa3.jpg 


3. Example


If) D = 2
Ex123.jpg
Ex4342e.jpg
Ex3g3le.jpg
Exam134gggge.jpg


4. Conclusion


      Downsampling reduces the magnitude by a factor of D, and increases the width of signals by D in the frequency domain. Moreover, it repeats it's signals every 2π and to prevent aliasing, decimator needs a lowpass filter before the downsampling.

Alumni Liaison

BSEE 2004, current Ph.D. student researching signal and image processing.

Landis Huffman