Drone-based Quantum Key Distribution (QKD)

Presently, Unmanned Arial Vehicles (UAVs) are being leveraged in numerous applications and industries, and their use is expected to increase in the future. In this effort, we present progress towards demonstrating Decoy-State Quantum Key Distribution (QKD) between two drones in flight. A significant challenge includes achieving system performance under compact Size, Weight, and Power (SWaP) constraints. We introduce and evaluate critical subsystems including a compact QKD source based on resonant-cavity Light Emitting Diodes (LED) controlled by an FPGA. The Pointing, Acquisition and Tracking (PAT) system provides course and fine alignment using gimbals, and fast steering mirrors, respectively. We discuss both transmit and receive optics including custom designed 3D-printed optical benches. Finally, we introduce single-photon detectors, FPGA-based time-tagger, and a novel statistical post-processing synchronization algorithm.