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arXiv · 0904.0307

Capacity with energy constraint in coherent state channel

Masahito Hayashi
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Abstract

We consider two kind of energy constraints when the output state is a coherent state. One is a constraint on the total energy during a fixed period; the other is a constraint on the total energy for a single code. The first setting can be easily dealt with by using the conventional capacity formula. The second setting requires the general capacity formula for a classical-quantum channel.

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Masahito Hayashi. 2009-04-02. Capacity with energy constraint in coherent state channel. https://doi.org/10.1109/tit.2010.2050805

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