Improved signal throughput in optical OFDM using hybrid optimization algorithms
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Shashi Raj K
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Sunil Devidas Bobade
Abstract
Optical orthogonal frequency division multiplexing (Optical OFDM) is a key modulation technique for high-speed optical communication systems; however, its performance is significantly degraded by chromatic dispersion and phase noise, which impair subcarrier orthogonality and introduce inter-symbol and inter-carrier interference. To overcome these limitations, this work proposes an enhanced signal detection scheme for optical OFDM based on a hybrid equalization framework integrated with quasi-reduced maximum likelihood detection (QRM-MLD). The proposed approach is evaluated against conventional detection methods, including zero-forcing equalization, minimum mean square error, maximum likelihood, and successive interference cancellation. MATLAB-based simulation results demonstrate that the hybrid QRM-MLD scheme achieves substantial performance gains under various channel impairment conditions. At a target bit error rate of 10−3, the proposed method requires up to 10 dB lower signal-to-noise ratio compared to uncompensated optical OFDM and offers approximately 2–7 dB improvement over conventional detection schemes. Capacity analysis further confirms its superiority, achieving a value of 290 at an SNR of 50 dB. Overall, the proposed hybrid detection strategy significantly improves detection accuracy, spectral efficiency, and robustness, making it a strong candidate for next-generation high-capacity optical OFDM communication systems.
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Research ethics: Not applicable.
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Informed consent: Not applicable.
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Author contributions: The authors have accepted responsibility for the entire content of this manuscript and approved its submission.
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Use of Large Language Models, AI and Machine Learning Tools: None declared.
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Conflict of interest: The authors state no conflict of interest.
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Research funding: Not applicable.
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Data availability: Not applicable.
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