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arXiv · 2511.05173

Performance Analysis of One- and Two-way DV-QKD with MIMO FSO Communication Systems

Sushil Kumar·Soumya P. Dash·George C. Alexandropoulos
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Abstract

This paper considers a multiple-input multiple-output (MIMO) wireless system wherein two legitimate users attempt to exchange secret keys over free-space optical (FSO) channels. Novel frameworks for the use of the one- and two-way discrete-variable quantum key distribution (DV-QKD) protocols, employing weak coherent pulses and decoy states, are presented. Focusing on the case where a photon-number-splitting attack is adopted by the eavesdropper and the legitimate multi-antenna receiver using threshold detection for the key extraction, novel expressions for the secret key rate and quantum bit error rate for both one- and two-way protocols are derived. The performance gain with larger MIMO configurations and the tradeoff between the performances with the one- and the two-way protocols with respect to the transmission distance of the legitimate FSO link are numerically assessed.

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Sushil Kumar, Soumya P. Dash, George C. Alexandropoulos. 2025-11-07. Performance Analysis of One- and Two-way DV-QKD with MIMO FSO Communication Systems. https://arxiv.org/abs/2511.05173

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