(New page: Saving location for potential formula sheet. <math>W_{N}^{kn} = e^{-j\frac{2\pi}{N}kn}</math>)
 
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Saving location for potential formula sheet.
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! ! style="background: rgb(228, 188, 126) none repeat scroll 0% 0%; -moz-background-clip: -moz-initial; -moz-background-origin: -moz-initial; -moz-background-inline-policy: -moz-initial; font-size: 110%;" colspan="2" | Potentially Useful Formulae
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|-
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| align="right" style="padding-right: 1em;" |
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| <math>\sum_{n=-\infty}^{\infty} a^n = \frac{1}{1-a}, \ |a|<1</math>
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| <math>\sum_{n=0}^{N-1} a^n = \frac{1-a^N}{1-a}, \ |a|<1</math>
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|-
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| align="right" style="padding-right: 1em;" |
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| <math>W_{N}^{kn} = e^{-j\frac{2\pi}{N}kn}</math>
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|-
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| align="right" style="padding-right: 1em;" | Euler's Formula
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| <math>e^{j\omega} = cos(\omega) + j sin(\omega)</math>
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|-
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| align="right" style="padding-right: 1em;" |
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| <math>cos(\omega) = \frac{e^{j\omega} + e^{-j\omega}}{2}</math>
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| <math>sin(\omega) = \frac{e^{j\omega} - e^{-j\omega}}{2j}</math>
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|-
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| align="right" style="padding-right: 1em;" | DFT
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| <math>X[k] = \sum_{n=0}^{N-1} x[n]e^{-j\frac{2\pi}{N}kn}</math>
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|-
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| align="right" style="padding-right: 1em;" | IDFT
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| <math>x[n] = \frac{1}{N} \sum_{k=0}^{N-1} X[k] e^{j\frac{2\pi}{N}kn}</math>
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|-
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| align="right" style="padding-right: 1em;" | DTFT
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| <math>X(\omega) = \sum_{n=-\infty}^{\infty} x[n]e^{-j\omega n}</math>
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|-
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| align="right" style="padding-right: 1em;" | IDTFT
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| <math>x[n] = \frac{1}{2\pi} \int_{-\pi}^{\pi} X(\omega) e^{j\omega n} d\omega</math>
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|-
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| align="right" style="padding-right: 1em;" | Z-Transform
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| <math>X(z) = \sum_{n=-\infty}^{\infty} x[n]z^{-n}</math>
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|-
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| align="right" style="padding-right: 1em;" | Time Shift Property of Z-Transform
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| <math>x[n-n_0] => X(z)z^{-n_0}</math>
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|-
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| align="right" style="padding-right: 1em;" | Comb/Rep
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| <math>rep_{T}(x(t)) = \sum_{k=-\infty}^{\infty} x(t-kT)</math>
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|-
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| align="right" style="padding-right: 1em;" | Comb/Rep
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| <math>comb_{T}(x(t)) = \sum_{k=-\infty}^{\infty} x(kT)\delta (t-kT)</math>
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|-
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| align="right" style="padding-right: 1em;" | Comb/Rep
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| <math>rep_{T}(x(t)) <=> \frac{1}{T} comb_{\frac{1}{T}}(X(f))</math>
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|-
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| align="right" style="padding-right: 1em;" | Comb/Rep
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| <math>comb_{T}(x(t)) <=> \frac{1}{T} rep_{\frac{1}{T}}(X(f))</math>
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|-
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| align="right" style="padding-right: 1em;" | Circular Convolution
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| <math>f[n]*_N g[n] = \sum_{k=0}^{N-1} f[k]g[(n-k)mod \ N]</math>
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|-
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| align="right" style="padding-right: 1em;" | Short Time Fourier Transform
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| <math>X[k,m] = \sum_{n=-\infty}^{\infty} x[n]w[n-m]e^{-j\frac{2\pi}{N}kn}</math>
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|-
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| align="right" style="padding-right: 1em;" | CSFT
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| <math>f(x,y) <=> F(u,v) = \int_{-\infty}^{\infty} \int_{-\infty}^{\infty} f(x,y)e^{-j2\pi(ux+vy)} \ dx dy</math>
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|-
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| align="right" style="padding-right: 1em;" | ICSFT
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| <math>F(u,v) <=> f(x,y) = \int_{-\infty}^{\infty} \int_{-\infty}^{\infty} F(u,v)e^{j2\pi (ux+vy)} \ du dv</math>
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|-
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| align="right" style="padding-right: 1em;" | Acoustic Pressure (outside last tube)
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| <math>b(t) = \frac{\rho c}{A_k}</math>
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|-
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| align="right" style="padding-right: 1em;" | Total acoustic Pressure (inside first tube)
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| <math>u(t) = (r+l)\frac{\rho c}{A_k}</math>
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|-
  
<math>W_{N}^{kn} = e^{-j\frac{2\pi}{N}kn}</math>
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----
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[[2010 Fall ECE 438 Boutin|Back to ECE438 Fall 2010 Prof. Boutin]]

Revision as of 09:22, 1 December 2010


Back to ECE438 Fall 2010 Prof. Boutin

Potentially Useful Formulae
$ \sum_{n=-\infty}^{\infty} a^n = \frac{1}{1-a}, \ |a|<1 $ $ \sum_{n=0}^{N-1} a^n = \frac{1-a^N}{1-a}, \ |a|<1 $
$ W_{N}^{kn} = e^{-j\frac{2\pi}{N}kn} $
Euler's Formula $ e^{j\omega} = cos(\omega) + j sin(\omega) $
$ cos(\omega) = \frac{e^{j\omega} + e^{-j\omega}}{2} $ $ sin(\omega) = \frac{e^{j\omega} - e^{-j\omega}}{2j} $
DFT $ X[k] = \sum_{n=0}^{N-1} x[n]e^{-j\frac{2\pi}{N}kn} $
IDFT $ x[n] = \frac{1}{N} \sum_{k=0}^{N-1} X[k] e^{j\frac{2\pi}{N}kn} $
DTFT $ X(\omega) = \sum_{n=-\infty}^{\infty} x[n]e^{-j\omega n} $
IDTFT $ x[n] = \frac{1}{2\pi} \int_{-\pi}^{\pi} X(\omega) e^{j\omega n} d\omega $
Z-Transform $ X(z) = \sum_{n=-\infty}^{\infty} x[n]z^{-n} $
Time Shift Property of Z-Transform $ x[n-n_0] => X(z)z^{-n_0} $
Comb/Rep $ rep_{T}(x(t)) = \sum_{k=-\infty}^{\infty} x(t-kT) $
Comb/Rep $ comb_{T}(x(t)) = \sum_{k=-\infty}^{\infty} x(kT)\delta (t-kT) $
Comb/Rep $ rep_{T}(x(t)) <=> \frac{1}{T} comb_{\frac{1}{T}}(X(f)) $
Comb/Rep $ comb_{T}(x(t)) <=> \frac{1}{T} rep_{\frac{1}{T}}(X(f)) $
Circular Convolution $ f[n]*_N g[n] = \sum_{k=0}^{N-1} f[k]g[(n-k)mod \ N] $
Short Time Fourier Transform $ X[k,m] = \sum_{n=-\infty}^{\infty} x[n]w[n-m]e^{-j\frac{2\pi}{N}kn} $
CSFT $ f(x,y) <=> F(u,v) = \int_{-\infty}^{\infty} \int_{-\infty}^{\infty} f(x,y)e^{-j2\pi(ux+vy)} \ dx dy $
ICSFT $ F(u,v) <=> f(x,y) = \int_{-\infty}^{\infty} \int_{-\infty}^{\infty} F(u,v)e^{j2\pi (ux+vy)} \ du dv $
Acoustic Pressure (outside last tube) $ b(t) = \frac{\rho c}{A_k} $
Total acoustic Pressure (inside first tube) $ u(t) = (r+l)\frac{\rho c}{A_k} $

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