Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: PAM-6 Coded Modulation for IM/DD Channels with a Peak-Power Constraint   Coded modulation with probabilistic amplitude shaping (PAS) is considered for
intensity modulation/direct detection channels with a transmitter peak-power
constraint. PAS is used to map bits to a uniform PAM-6 distribution and
outperforms PAM-8 for rates up to around 2.3 bits per channel use. PAM-6 with
PAS also outperforms a cross-shaped QAM-32 constellation by up to 1 dB and 0.65
dB after bit-metric soft- and hard decoding, respectively. An alternative PAM-6
scheme based on a framed cross-shaped QAM-32 constellation is proposed that
shows similar gains.

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The categories of this paper are: econ
27
The categories of this paper are: comp-gas
10
The categories of this paper are: q-bio
11
The categories of this paper are: hep-lat
9
The categories of this paper are: nlin
28
The categories of this paper are: alg-geom
6
The categories of this paper are: astro-ph
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The categories of this paper are: quant-ph
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The categories of this paper are: stat
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The categories of this paper are: plasm-ph
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The categories of this paper are: funct-an
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The categories of this paper are: q-alg
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The categories of this paper are: mtrl-th
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The categories of this paper are: chao-dyn
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The categories of this paper are: solv-int
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The categories of this paper are: chem-ph