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arXiv · 2607.09433

On LLR Calculations for Soft-decision Decoding in Next-generation IM-DD Systems with Laser RIN

Felipe Villenas·Yunus Can Gültekin·Alex Alvarado
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Abstract

We propose a low-complexity LLR approximation for SD decoding in IM-DD systems with relative intensity noise. Our approximation results in no BER performance penalty for a concatenated KP4+Hamming FEC scheme, and outperforms mismatched AWGN-based LLRs.

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Felipe Villenas, Yunus Can Gültekin, Alex Alvarado. 2026-07-10. On LLR Calculations for Soft-decision Decoding in Next-generation IM-DD Systems with Laser RIN. https://arxiv.org/abs/2607.09433

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