This letter theoretically proposes and experimentally demonstrates a high-security optical access network (OAN) scheme based on carrier-less amplitude and phase modulation (CAP). The double chaotic map is used to perform the floating probabilistic shaping (PS), so as to encrypt data in the physical layer. 20 Gb/s encrypted data transmission was successfully realized employing 16-CAP modulation. The experimental results show that the proposed scheme displays high sensitivity and security, as well as good bit error ratio (BER) performance when combined with PS technology, thus presenting a promising prospect for future secure OAN.

中文翻译：

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基于浮动概率扰动的CAP-PON系统高安全物理层

这封信从理论上提出并通过实验证明了一种基于无载波幅度和相位调制（CAP）的高安全性光接入网络（OAN）方案。双混沌映射用于执行浮动概率整形（PS），从而对物理层中的数据进行加密。采用 16-CAP 调制成功实现了 20 Gb/s 加密数据传输。实验结果表明，所提出的方案在与PS技术结合时表现出较高的灵敏度和安全性，以及良好的误码率（BER）性能，为未来的安全OAN带来了广阔的前景。