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Optical Fiber Communication Conference

Comparative performance of DV- and CV-QKD in Co-propagation with S+C+L-band WDM Signals

Hiroki Kawahara, Tetsuo Kawakami, Toshihiko Okamura, Naoto Ishii

Published Jan 1, 2026• 0 citations
Publisher

Abstract

Using an ISRS/SpRS-aware model, we numerically compare decoy-state BB84 and four-state CV-QKD co-propagating with ultra-wideband WDM signals, showing CV-QKD achieves higher co-propagation efficiency defined by a normalized product of secret-key rate and WDM capacity.
DOI
10.1364/ofc.2026.th2a.73

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