High-Security Physical Layer in CAP-PON System Based on Floating Probability Disturbance

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.