In this paper, we propose a novel 3-dimension multi wings chaotic encryption scheme for PAM-DMT-based optical wireless access network. In our proposed scheme, one dimension (x) is used for XOR operation, one dimension (y) is used for confusion of PAM signal's amplitude and one dimension (z) is use for DMT subcarrier scrambling. We experimentally demonstrate the 3-dimension multi wings chaotic encryption scheme in PAM4-DMT optical access network. The experimental results show that our proposed scheme can effectively enhance physical-layer transmission security and simultaneously improve transmission performance. What is more, the proposed scheme has good scalability. It can be extended to high order PAM-DMT system and can use more wings to enlarge the key space. To verify the effectiveness of the scheme for practical application, encrypted transmission of a digital image in 60 km SMMF is demonstrated.

中文翻译：

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基于PAM-DMT的光接入网多翼混沌加密方案

在本文中，我们为基于 PAM-DMT 的光无线接入网络提出了一种新颖的 3 维多翼混沌加密方案。在我们提出的方案中，一维 (x) 用于 XOR 运算，一维 (y) 用于混淆 PAM 信号的幅度，一维 (z) 用于 DMT 子载波加扰。我们通过实验证明了 PAM4-DMT 光接入网络中的 3 维多翼混沌加密方案。实验结果表明，我们提出的方案可以有效增强物理层传输安全性，同时提高传输性能。更重要的是，所提出的方案具有良好的可扩展性。可以扩展到高阶PAM-DMT系统，可以使用更多的翅膀来扩大密钥空间。为了验证该方案在实际应用中的有效性，