Secure practical indoor optical wireless communications using quantum key distribution

TL;DR

This paper explores a new spectral region around 1370 nm for quantum key distribution in indoor optical wireless environments, demonstrating its feasibility through simulation and analysis, and addressing challenges posed by ambient light.

Contribution

It introduces the 1370 nm absorption band as a novel wavelength region for practical indoor QKD, supported by simulations and ambient light measurements.

Findings

1370 nm is a viable spectral region for indoor QKD.

Approximately 20 dB SNR is needed for feasible QKD links.

Maximum QBER of 11% with BB84 protocol is achievable.

Abstract

Quantum Key Distribution (QKD) can guarantee security for practical indoor optical wireless environments. The key challenges are to mitigate artificial lighting and ambient light at the receiver. A new spectral region for QKD is proposed and an ideal QKD link model is simulated with experimental ambient light power measurements. Simulation, modelling, and analysis indicates that the carbon dioxide and water absorption band (1370 nm) is a new wavelength region for QKD operation in indoor optical wireless environments. For a feasible QKD link, approximately 20 dB of signal to noise ratio (SNR) is required and a maximum quantum bit error rate (QBER) of 11% when using the BB84 protocol. Links in the new spectral region with a FOV of several degrees are feasible, depending on available components.