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The Poisson Channel at Low Input Powers

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 نشر من قبل Ligong Wang
 تاريخ النشر 2008
  مجال البحث الهندسة المعلوماتية
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The asymptotic capacity at low input powers of an average-power limited or an average- and peak-power limited discrete-time Poisson channel is considered. For a Poisson channel whose dark current is zero or decays to zero linearly with its average input power $E$, capacity scales like $Elogfrac{1}{E}$ for small $E$. For a Poisson channel whose dark current is a nonzero constant, capacity scales, to within a constant, like $Eloglogfrac{1}{E}$ for small $E$.

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