Performance Analysis of Underwater Optical Communications: Application to the BBM92 Quantum Key Distribution Protocol

Nour Rizk, Angélique Drémeau, Arnaud Coatanhay

Published Aug 31, 2026• 0 citations

Abstract

In the context of secure underwater optical communications, this study examines the performance of the entanglement-based BBM92 protocol when the source generates non-maximally entangled photon pairs. The impact of seawater optical properties, as well as source correlation characteristics, on transmission efficiency is analyzed for three types of nonturbulent channels: clear, coastal, and turbid water. The main performance metrics, including quantum bit error rate (QBER), secret key rate (SKR), and correlation probability, are analytically derived and evaluated as functions of transmission distance between two communicating parties. Monte Carlo simulation results validate our analytical models and quantify performance under different channel conditions.

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