Nuclear Science and Techniques

《核技术》(英文版) ISSN 1001-8042 CN 31-1559/TL     2019 Impact factor 1.556

Nuclear Science and Techniques ›› 2016, Vol. 27 ›› Issue (1): 15 doi: 10.1007/s41365-016-0012-y


TDC-GPX-based synchronization scheme for QKD system

Lian-Jun Jiang 1,2, Shi-Biao Tang 1,2, Ze-Jie Yin1,2   

  1. 1. State Key Laboratory of Particle Detection and Electronics, University of Science and Technology of China, Hefei, 230026, China
    2. Department of Modern Physics, University of Science and Technology of China, Hefei, 230026, China
Lian-Jun Jiang, Shi-Biao Tang, Ze-Jie Yin. TDC-GPX-based synchronization scheme for QKD system.Nuclear Science and Techniques, 2016, 27(1): 15     doi: 10.1007/s41365-016-0012-y


To meet the needs of signal alignment between the transmitter and receiver in a quantum key distribution (QKD) system, we put forward a TDC-GPX-based synchronization scheme, which is based on high-precision time measurement. We send a low-frequency repeat optical pulse synchronized with associated quantum signals on the receiver’s side by using a time-to-digital converter (TDC) module, the time intervals between quantum signals, and synchronization signals measured and converted to corresponding temporal orders to complete the synchronization. We state the principle of the synchronization scheme in detail and then verify it in an actual QKD test bed. The test results show that our TDC-GPX-based synchronization can obtain a time resolution better than 100 ps, and the proposed scheme shows full feasibility for an actual QKD system.

Key words: Quantum key distribution, Synchronization, Time-to-digital converter, TDC-GPX, Time measurement