Abstract. A probabilistically shaped 9-ary carrierless amplitude and phase (CAP-9) optical modulation format based on a reverse distribution model is proposed. We experimentally demonstrate the transmission of 33.3-Gb / s PS-CAP-9 signals over 25-km standard single-mode fiber in an intensity-modulation and direct-detection system. The results indicate that the proposed scheme outperforms the conventional uniform CAP-16 and the conventional PS-CAP-16 in receiver sensitivity by 1.2 and 0.4 dB at the threshold of 3.8 × 10 − 3 BER, respectively.

中文翻译：

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基于反向分布模型的概率形状 CAP-9 传输

摘要。提出了一种基于反向分布模型的概率整形9元无载波幅度和相位(CAP-9)光调制格式。我们在强度调制和直接检测系统中通过实验证明了 33.3-Gb/s PS-CAP-9 信号在 25 公里标准单模光纤上的传输。结果表明，在 3.8 × 10 - 3 BER 的阈值下，所提出的方案在接收器灵敏度方面分别优于传统的统一 CAP-16 和传统的 PS-CAP-16 1.2 和 0.4 dB。