Impact of Shot Noise Estimation on the Secret Key Rate of a CV-QKD System

  • Daniel Pereira University of Aveiro
  • Nuno A. Silva University of Aveiro
  • Armando N. Pinto University of Aveiro


In this work we present the impact of the uncertainty of the shot noise estimate on the performance of a continuous variables quantum key distribution system using a probabilistically shaped 128-APSK constellation. We demonstrate that the performance of the system is greatly degraded by the uncertainty of the shot noise estimate, with a total loss of security being possible.


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PEREIRA, Daniel; SILVA, Nuno A.; PINTO, Armando N.. Impact of Shot Noise Estimation on the Secret Key Rate of a CV-QKD System. In: WORKSHOP DE COMUNICAÇÃO E COMPUTAÇÃO QUÂNTICA (WQUANTUM), 2. , 2022, Fortaleza. Anais [...]. Porto Alegre: Sociedade Brasileira de Computação, 2022 . p. 1-6. DOI: