Reconciliation for CV-QKD using globally-coupled LDPC codes

• 来源期刊: 中国物理B（英文版）
• 关键词: continuous-variable quantum key distribution globally coupled low-density parity-check recon-ciliation efficiency frame error rate
• 年，卷（期）: 2020,（4）
• 页码范围: 156-163
• 页数: 8页
• 语种: 英文
• DOI: 10.1088/1674-1056/ab6d4f

摘要

Reconciliation is a necessary step in postprocessing of continuous-variable quantum key distribution (CV-QKD) sys-tem. We use globally coupled low-density parity-check (GC-LDPC) codes in reconciliation to extract a precise secret key from the raw keys over the authenticated classical public channel between two users. GC-LDPC codes have excellent per-formance over both the additive Gaussian white noise and binary-erasure channels. The reconciliation based on GC-LDPC codes can improve the reconciliation efficiency to 95.42％and reduce the frame error rate to 3.25×10-3. Using distillation, the decoding speed can achieve 23.8 Mbits/s and decrease the cost of memory. Given decoding speed and low memory usage, this makes the proposed reconciliation method viable approach for high-speed CV-QKD system.