A Novel Resource-Efficient Privacy Amplification Scheme: Towards Ground-Satellite Quantum Key Distribution Post-processing

Abstract

Quantum key distribution (QKD) provides the intrinsically unconditional secure method to generate and transfer cryptographic keys based on laws of quantum mechanics. The introduction of QKD technology in satellite communications has changed the way to understand them, permitting secure and reliable global communications. In a real-life situation, however, ground-satellite QKD needs to handle a critical issue: the problem of on-board resource insufficiency. Privacy amplification (PA) determining the final key rate is a significant procedure in QKD post-processing. Though fast Fourier transform (FFT) technology can expedite PA procedure, it costs more computing and storage resources. With a novel division and aggregation scheduling (DAS) policy, we made some modifications to FFT implementation and proposed a resource-efficient PA scheme (called as DAS-FFT PA), which efficiently reduces the resource overhead of implementing overall PA module. Our experimental results demonstrate and confirm that our proposed scheme fulfills the expected target.