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Cyclops Array

  1. Aug 25, 2008 #1
    I am just "trying" to watch interstellar TV...

    The detection range in lightyears is
    [tex]R = \sqrt{\frac{\text{EIRP}\cdot A_{e}_{r}\cdot\text{twc}}{4\pi\cdot\text{SNR}\cdot B_{r}\cdot k_{B}\cdot T_{sys}}}\cdot\frac{1\,\text{ly}}{9454254955488000\,\text{m}}[/tex], where
    [tex]\text{EIRP} = P_{t}G_{t},[/tex]
    [tex]\text{twc} = \sqrt{B_{r}t} = 1\,\text{for modulated signals,}[/tex]
    [tex]\text{SNR}[/tex] is signal-to-noise ratio,
    [tex]A_{e}_{r}[/tex] is receiver's radio telescope's effective area,
    [tex]B_{r}[/tex] is receiver's bandwidth which is larger or equal to transmitters bandwidth,
    [tex]k_{B}[/tex] is Boltzmann's constant and
    [tex]T_{sys}[/tex] is system's temperature in Kelvins.

    I put these numbers in:
    [tex]\text{EIRP} = 15000\,\text{W}[/tex],
    [tex]A_{e}_{r} = 15707963\,\text{m}^{2}[/tex],
    [tex]\text{twc} = 1[/tex],
    [tex]\text{SNR} = 22[/tex],
    [tex]B_{r} = 8\cdot 10^{6}\,\text{Hz}[/tex],
    [tex]k_{b} = 1.3806504\cdot 10^{-23}\,\text{J/K}[/tex], and
    [tex]T_{sys} = 10\,\text{K}[/tex].
    I get: [tex]R = 0.000093\,\text{ly}.[/tex]

    1. Is the equation correct?
    2. Is my answer about correct?
    3. How to reduce the SNR?
    4. How to reduce the system temperature?
    5. Can I really rise the detection range just only reducing the system temperature? So technically I can watch interstellar TV shows with a very, very small disc, if I can go to very near the absolute zero?
    Last edited: Aug 25, 2008
  2. jcsd
  3. Aug 26, 2008 #2
    Guys? Anyone?

    [tex]P_{t}[/tex] is transmitter's power.
    [tex]G_{t}[/tex] is transmitter's antenna gain.
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