Optics Express

Security-enhanced ultra-high-order QAM quantum noise stream cipher assisted by intensity and phase chaotic encryption

Lin Jiang, Sijia Gu, Lianshan Yan, Jihui Sun, Jiacheng Feng, Anlin Yi, Wei Pan, Bin Luo

Published May 23, 2025• 5 citations

Abstract

An ultra-high-order QAM quantum noise stream cipher (QNSC) scheme assisted by intensity and phase chaotic encryption is proposed. In this scheme, the legal transmitter (Alice) first encrypts the original low-order QAM signal into an ultra-high-order QAM signal according to the pre-shared seed key based on the Y-00 protocol, and then conceals the intensity and phase information of the ultra-high-order QAM signal through the intensity and phase chaos generated from a nonlinear delay chaotic source for enhancing the security. The intensity and phase chaotic carrier can be eliminated by the open-loop chaotic synchronization module at the legal receiver (Bob). The scheme was numerically verified in 112 Gbit/s (28 GBaud 16QAM plaintext) and 168 Gbit/s (28 GBaud 64QAM plaintext) 65536QAM/QNSC systems, which can achieve 600 km and 150 km transmission at 7% HD-FEC threshold, and 1000 km and 350 km transmission at 20% SD-FEC threshold, respectively. Meanwhile, the number of masked signals (NMS) and the detection failure probability (DFP) in the scheme are obviously higher than in the original QAM/QNSC system. We believe that the proposed scheme is a promising strategy for enhancing the security of QAM/QNSC transmission systems.

DOI: 10.1364/oe.557873

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