{"ID":6497670,"CreatedAt":"2026-07-13T01:19:40.13847098Z","UpdatedAt":"2026-07-14T01:36:59.12045529Z","DeletedAt":null,"paper_url":"https://arxiv.org/abs/2607.09433","arxiv_id":"2607.09433","title":"On LLR Calculations for Soft-decision Decoding in Next-generation IM-DD Systems with Laser RIN","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.","short_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.","url_abs":"https://arxiv.org/abs/2607.09433","url_pdf":"https://arxiv.org/pdf/2607.09433v1","authors":"[\"Felipe Villenas\",\"Yunus Can Gültekin\",\"Alex Alvarado\"]","published":"2026-07-10T13:58:25Z","proceeding":"eess.SP","tasks":"[\"eess.SP\"]","methods":"[]","has_code":false}