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Transmission of Multiple Signals through an Optical Fiber Using Wavefront Shaping
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Ultra-high-order QAM modulation approach based on local constellation decomposition joint shaping

Ying Zhang, Jiaqi Wang, Wenxiang Yao

    Optics Express
    |December 19, 2025
    PubMed
    Summary

    This study introduces a novel joint shaping scheme for ultra-high-order Quadrature Amplitude Modulation (QAM) signals, improving bit error rate (BER) performance in intensity modulation direct detection (IMDD) systems using Delta-sigma modulation (DSM). The method enhances receiver sensitivity and system efficiency.

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