Ensuring high speed physical layer confidential data exchange in classical optical fiber channels is a critical challenge. In this letter, we experimentally demonstrated a physical secure optical communication system based on temporal spreading-then-random phase encryption scheme for secure transmission of 25 Gb/s intensity-modulated signal. Commercial low cost continuous-wave laser is employed as the optical source, and a chirped fiber Bragg grating followed by a phase modulator is utilized as a two-dimensional encryption module. Successful encryption and decryption of 25 Gb/s confidential data have been achieved by optimizing optical hardware parameters. The demonstrated system can combine the advantages of hardware and digital encryption, exhibiting great potential for providing physical layer security in future high-speed secure optical communication systems.

中文翻译：

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基于时间扩展-然后-随机相位加密的 25 Gb/s 物理安全通信

确保经典光纤通道中的高速物理层机密数据交换是一项关键挑战。在这封信中，我们通过实验证明了一种基于时间扩展然后随机相位加密方案的物理安全光通信系统，用于安全传输 25 Gb/s 强度调制信号。采用商用低成本连续波激光器作为光源，利用啁啾光纤布拉格光栅和相位调制器作为二维加密模块。通过优化光硬件参数，实现了25Gb/s机密数据的成功加解密。演示的系统可以结合硬件和数字加密的优点，