(Undo revision 67674 by Skwon (Talk))
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     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.
 
     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.
  
where <br>
 
  
<math>s_D [m]=\left\{ \begin{array}{ll}
 
1,& \text{ if } n \text{ is a multiple of } 4,\\
 
0, & \text{ else}.
 
\end{array}\right. = {\frac{1}{D}} \sum_{k = -\infty}^{D-1} e^{jk {\frac{2 \pi}{D} m}}</math>
 
  
 
== Derivation  ==
 
== Derivation  ==
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<font size="3"></font>  
 
<font size="3"></font>  
 
<font size="3">To summarize, the Nyquist theorem states that any bandlimited signal can be perfectly reconstructed from its sampling if sampled at a rate greater than twice its bandwidth <span class="texhtml">(''f''<sub>''s''</sub> &gt; 2''f''<sub>''M''</sub>)</span>. However, the Nyquist condition is not necessary for perfect reconstruction as shown in the example above. </font>
 
  
 
<font size="3"></font>  
 
<font size="3"></font>  

Revision as of 19:35, 9 October 2014


Downsampling

A slecture by ECE student Yerkebulan Yeshmukhanbetov

Partly based on the ECE438 Fall 2014 lecture material of Prof. Mireille Boutin.


Outline

  1. Introduction
  2. Derivation
  3. Example
  4. Conclusion
  5. References

Introduction

    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.


Derivation

Example




Example


Conclusion


References

Alumni Liaison

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

Landis Huffman