Chinese Optics Letters, 2016, 14 (7): 070602, Published Online: Aug. 3, 2018
Simultaneous frequency transfer and time synchronization over a 430 km fiber backbone network using a cascaded system
Abstract
Based on dense wavelength-division multiplexing technology, frequency transfer and time synchronization are simultaneously realized over a compensated cascaded fiber link of 430 km, which is a part of the Beijing–Shanghai optical fiber backbone network. The entire cascaded system consists of two stages with fiber links of 280 and 150 km, respectively. To keep high symmetry and low noise, specific bi-directional erbium-doped fiber amplifiers are used to compensate the large optical attenuation of each fiber link. When the compensation servo is active in every stage, the cascaded system achieves the stability of 1.94 × 10 13 at 1 s and 1.34 × 10 16 at 10 4 s , for frequency transfer. It is also verified that the actual results of the cascaded system are in good agreement with the theoretical ones calculated from error theory. Simultaneously, after calibration of each stage, time synchronization is also realized. The final accuracy of the whole system is within 94 ps.
Qin Liu, Shenglong Han, Jialiang Wang, Zitong Feng, Wei Chen, Nan Cheng, Youzhen Gui, Haiwen Cai, Shensheng Han. Simultaneous frequency transfer and time synchronization over a 430 km fiber backbone network using a cascaded system[J]. Chinese Optics Letters, 2016, 14(7): 070602.