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= Table of CT Fourier series coefficients and properties =
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= Table of CT Fourier Series Coefficients and Properties =
  
::You may want to switch the titles of the second and third column. -pm
 
 
== Some Fourier series ==
 
== Some Fourier series ==
  
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== Properties  of CT Fourier systems ==
 
== Properties  of CT Fourier systems ==
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{| border="1" class="wikitable"
 
{| border="1" class="wikitable"
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| x(t), y(t) are periodic with period T
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| <math>a_k</math> for x(t) and <math>b_k</math> for y(t)
 
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| Linearity
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| <math>Ax(t)+By(t)</math>
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| <math>Aa_k+Bb_k</math>
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| Time Shifting
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| <math>x(t-t_0)</math>
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| <math>e^{-j k \omega_0 t_0}a_k = e^{-j k \frac{2\pi}{T}t_0}a_k</math>
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|-
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| Frequency Shifting
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| <math>e^{jM\omega_0t}x(t) = e^{jM\frac{2\pi}{T}t}x(t)</math>
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| <math>a_k-M</math>
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| Conjugation
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| <math>x^*(t)</math>
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| <math>a^*_{(-k)}</math>
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| Time Reversal
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| <math>x(-t)</math>
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| <math>a_{(-k)}</math>
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| Time scaling
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| <math>x(ct), c < 0,</math> periodic with period T/c
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| <math>a_k</math>
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| Multiplication
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| <math>x(t)y(t)</math>
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| <math>\sum_{l=-\infty}^\infty a_l b_{k-l}</math>
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| Differentiation
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| <math>\frac{dx(t)}{dt}</math>
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| <math>jk\omega_0a_k=jk\frac{2\pi}{T}a_k</math>
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| Real and Even Signals
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| <math class="inline">x(t)</math> real and even
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| <math class="inline">a_k</math> real and even
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| Real and Odd Signals
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| <math class="inline">x(t)</math> real and odd
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| <math class="inline">a_k</math> purely imaginary and odd
 
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== Parseval's Relation ==
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<math>\frac{1}{T}\int_T \Big| x(t) \Big| ^2 dt = \sum_{k=-\infty}^\infty \Big| a_k \Big| ^2</math>
  
 
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[[2011_Spring_ECE_301_Boutin|Back to ECE301 Spring 2011 Prof. Boutin]]
 
[[2011_Spring_ECE_301_Boutin|Back to ECE301 Spring 2011 Prof. Boutin]]
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--[[User:Cmcmican|Cmcmican]] 19:02, 28 March 2011 (UTC)

Latest revision as of 09:52, 6 May 2012


Table of CT Fourier Series Coefficients and Properties

Some Fourier series

Function Fourier Series Coefficients
$ sin(w_0t) $ $ \frac{1}{2j}e^{jw_0t}-\frac{1}{2j}e^{-jw_0t} $ $ a_1=\frac{1}{2j}, a_{-1}=\frac{-1}{2j}, a_k=0 \mbox{ for } k \ne 1,-1 $
$ cos(w_0t) $ $ \frac{1}{2}e^{jw_0t}+\frac{1}{2}e^{-jw_0t} $ $ a_1=\frac{1}{2}, a_{-1}=\frac{1}{2}, a_k=0 \mbox{ for } k \ne 1,-1 $
periodic square wave

$ x(t)=\begin{cases} 1, & \mbox{if }t<T_1 \\ 0, & \mbox{if }T_1<t<T/2 \end{cases} $

where T is the period and $ 2T_1 $ is the width of the pulse

$ \sum_{k=1}^N k^2 a_k e^{jk(\frac{2\pi}{T})t} $

(just the normal formula)

$ a_k = \frac{2sin(k\omega_0T_1)}{k\omega_0T_1} $

Properties of CT Fourier systems

Property Periodic Signal Fourier Series Coefficients
x(t), y(t) are periodic with period T $ a_k $ for x(t) and $ b_k $ for y(t)
Linearity $ Ax(t)+By(t) $ $ Aa_k+Bb_k $
Time Shifting $ x(t-t_0) $ $ e^{-j k \omega_0 t_0}a_k = e^{-j k \frac{2\pi}{T}t_0}a_k $
Frequency Shifting $ e^{jM\omega_0t}x(t) = e^{jM\frac{2\pi}{T}t}x(t) $ $ a_k-M $
Conjugation $ x^*(t) $ $ a^*_{(-k)} $
Time Reversal $ x(-t) $ $ a_{(-k)} $
Time scaling $ x(ct), c < 0, $ periodic with period T/c $ a_k $
Multiplication $ x(t)y(t) $ $ \sum_{l=-\infty}^\infty a_l b_{k-l} $
Differentiation $ \frac{dx(t)}{dt} $ $ jk\omega_0a_k=jk\frac{2\pi}{T}a_k $
Real and Even Signals $ x(t) $ real and even $ a_k $ real and even
Real and Odd Signals $ x(t) $ real and odd $ a_k $ purely imaginary and odd


Parseval's Relation

$ \frac{1}{T}\int_T \Big| x(t) \Big| ^2 dt = \sum_{k=-\infty}^\infty \Big| a_k \Big| ^2 $


Back to ECE301 Spring 2011 Prof. Boutin

--Cmcmican 19:02, 28 March 2011 (UTC)

Alumni Liaison

Abstract algebra continues the conceptual developments of linear algebra, on an even grander scale.

Dr. Paul Garrett