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arXiv · 2104.14304

PAM-6 Coded Modulation for IM/DD Channels with a Peak-Power Constraint

Tobias Prinz·Thomas Wiegart·Daniel Plabst·Stefano Calabrò·Georg Böcherer·Nebojsa Stojanovic·Talha Rahman
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Abstract

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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Tobias Prinz, Thomas Wiegart, Daniel Plabst, Stefano Calabrò, Georg Böcherer, Nebojsa Stojanovic, Talha Rahman. 2021-04-29. PAM-6 Coded Modulation for IM/DD Channels with a Peak-Power Constraint. https://arxiv.org/abs/2104.14304

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