International Journal of Theoretical Physics

Channel Estimation and Carrier Detection for Multiuser Multicarrier Continuous-Variable Quantum Key Distribution

László Gyöngyösi, Sándor Imre

Published Apr 9, 2026• 0 citations

Abstract

Abstract A multicarrier continuous-variable quantum key distribution (CVQKD) protocol uses subcarrier quantum states and subchannels for the transmission. Here, a subchannel estimation and subcarrier detection method is defined for multiuser multicarrier continuous-variable quantum key distribution. The subcarrier spreading technique estimates the transmittance conditions of the subchannels with a theoretical error-minimum in the presence of a Gaussian noise. We study the performance of the method and address the implementation framework.

DOI: 10.1007/s10773-026-06321-5

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