International Conference on Intelligent Computing and System Simulation (ICSS)

Secret-key distribution over atmospheric wireless optical channels assisted by turbulence-induced fading scrambling

Qiong Li, Chunyi Chen, Bo Yu, Haiyang Yu

Published Dec 22, 2025• 0 citations

Abstract

Secret-key distribution leveraging the fading characteristics of wireless optical channels has attracted significant attention. To address the challenges of high-frequency sampling over slowly varying channels, a turbulence-induced fading scrambling-assisted key distribution scheme is proposed to enhance the randomness of shared keys. Combined with random modulation, the scheme enables legitimate parties to obtain more decorrelated wireless signal sequences. Additionally, a specialized interleave quantization (IQ) method is introduced to improve the statistical properties of the generated keys. The entire observation sequence is processed using IQ to mitigate the impact of large-scale slow channel variations. Simulation and experimental results demonstrate that the proposed scheme generates highly random original key sequences at high sampling frequencies without increasing the key disagreement rate (KDR). The final key sequence, incorporating random modulation and interleaving, is evaluated using the NIST test suite, yielding p-values greater than 0.01. These results confirm the effectiveness of the proposed scheme in generating statistically random shared secret keys under slowly varying wireless optical channels.

DOI: 10.1117/12.3092064

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