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Register a new userNo input symbol should occur more frequently than 1-1/e
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Added by
Alexandros Manolakos
Publication date
2012
fields
Informatics Engineering
and research's language is
English
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Consider any discrete memoryless channel (DMC) with arbitrarily but finite input and output alphabets X, Y respectively. Then, for any capacity achieving input distribution all symbols occur less frequently than 1-1/e$. That is, [ maxlimits_{x in mathcal{X}} P^*(x) < 1-frac{1}{e} ] oindent where $P^*(x)$ is a capacity achieving input distribution. Also, we provide sufficient conditions for which a discrete distribution can be a capacity achieving input distribution for some DMC channel. Lastly, we show that there is no similar restriction on the capacity achieving output distribution.
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