Fiber-optic joint time and frequency transfer with the same wavelength
Abstract
Optical fiber links have demonstrated their ability to transfer the ultra-stable clock signals. In this paper we propose and demonstrate a new scheme to transfer both time and radio frequency with the same wavelength based on coherent demodulation technique. Time signal is encoded as a binary phase-shift keying (BPSK) to the optical carrier using electro optic modulator (EOM) by phase modulation and makes sure the frequency signal free from interference with single pulse. The phase changes caused by the fluctuations of the transfer links are actively cancelled at local site by optical delay lines. Radio frequency with 1GHz and time signal with one pulse per second (1PPS) transmitted over a 110km fiber spools are obtained. The experimental results demonstrate that frequency instabilities of 1.7E-14 at 1s and 5.9E-17 at 104s. Moreover, time interval transfer of 1PPS signal reaches sub-ps stability after 1000s. This scheme offers advantages with respect to reduce the channel in fiber network, and can keep time and frequency signal independent of each other.
Cite
@article{arxiv.1909.03197,
title = {Fiber-optic joint time and frequency transfer with the same wavelength},
author = {Jialiang Wang and Chaolei Yue and Yueli Xi and Yanguang Sun and Nan Cheng and Fei Yang and Mingyu Jiang and Jianfeng Sun and Youzhen Gui and Haiwen Cai},
journal= {arXiv preprint arXiv:1909.03197},
year = {2020}
}