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Title: Security of Satellite-Based CV-QKD under Realistic Assumptions
With the vastly growing need for secure communication, quantum key distribution (QKD) has been developed to provide high security for communications against potential attacks from the fast-developing quantum computers. Among different QKD protocols, continuous variable (CV-) QKD employing Gaussian modulated coherent states has been promising for its complete security proof and its compatibility with current communication systems in implementation with homodyne or heterodyne detection. Since satellite communication has been more and more important in developing global communication networks, there have been concerns about the security in satellite communication and how we should evaluate the security of CV-QKD in such scenarios. To better analyse the secure key rate (SKR) in this case, in this invited paper we investigate the CV-QKD SKR lower bounds under realistic assumptions over a satellite-to-satellite channel. We also investigate the eavesdropper's best strategy to apply in these scenarios. We demonstrate that for these channel conditions with well-chosen carrier centre frequency and receiver aperture size, based on channel parameters, we can optimize SKR correspondingly. The proposed satellite-based QKD system provides high security level for the coming 5G and beyond networks, the Internet of things, self-driving cars, and other fast-developing applications.  more » « less
Award ID(s):
1907918
PAR ID:
10249505
Author(s) / Creator(s):
;
Date Published:
Journal Name:
2020 22nd International Conference on Transparent Optical Networks (ICTON)
Page Range / eLocation ID:
We.A2.1, 1 to 4
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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