公开(公告)号：US20250141671A1

公开(公告)日：2025-05-01

申请号：US18383723

申请日：2023-10-25

Applicant: NEC Corporation

Inventor： Tetsuo KAWAKAMI ,  Wakako Yasuda

IPC: H04L9/08

Abstract: A quantum key delivery system in which a first transmission device phase modulates a first polarization component of two orthogonal polarization components in transmitted light and modulates a second polarization component, which is the other polarization component, into a signal indicating the second random number sequence, based on a first random number sequence indicating the bit sequence to be transmitted and the second random number sequence indicating the base in the phase modulation of the bit sequence to be transmitted; and a second transmission device separates orthogonal polarization modes in the received light and extracts a clock timing from the signal indicating the second random number sequence.

公开(公告)号：US20240283638A1

公开(公告)日：2024-08-22

申请号：US18442142

申请日：2024-02-15

Applicant: NEC Corporation

Inventor： Wakako YASUDA ,  Tetsuo KAWAKAMI

IPC: H04L9/08

CPC classification number: H04L9/0852 ,  H04L9/0819 ,  H04L9/085

Abstract: Shared information generation technique including key generation rate and soft-decision error correction in CV-QKD is disclosed. A receiver is configured to: set reference bit positions for basis reconciliation according to the reference bit positions with a transmitter, to generate sifted key quantization data; performs hard decision on a part of the sifted key quantization data to generate hard-decision data; perform bit position synchronization decision whether bit position synchronization is established; and in response to establishment of bit position synchronization, performs soft-decision error correction processing to generate shared information.