{"title":"Multiple-Node Time Transfer Over Star Fiber Network Without Requiring Link Calibration","authors":"Kunfeng Xie;Liang Hu;Jianping Chen;Guiling Wu","doi":"10.1109/OJUFFC.2025.3541156","DOIUrl":null,"url":null,"abstract":"In this letter, we proposed a point-to-multipoint fiber-optic time transfer scheme over a star-shaped fiber network based on bidirectional frequency division multiplexing without requiring link calibration. The time signals at the local station and remote stations are encoded into time-varying signals within in different spectral passbands, respectively. The optical carriers with the same wavelength are employed to transfer the two time-varying signals in both directions over a single fiber. The backscattering noises from fiber links can be effectively suppressed by simply electrical filtering due to the non-overlapping on spectrum between the forward and backward time-varying signals. The local station broadcasts the time signal of the reference clock to all remote stations based on space division multiplexing to support point-to-multipoint fiber-optic time transfer. The proposed scheme is demonstrated over a star-shaped fiber network with two remote stations. The results show that the measured mean clock difference can be less than -1.03 ps and 4.99 ps without link calibration, respectively. The measured time stability in terms of time deviation is better than 19.93 ps@1s, 0.50 ps@1000s and 25.35 ps@1s, 0.65 ps@1000s.","PeriodicalId":73301,"journal":{"name":"IEEE open journal of ultrasonics, ferroelectrics, and frequency control","volume":"5 ","pages":"11-14"},"PeriodicalIF":0.0000,"publicationDate":"2025-02-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=10879779","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"IEEE open journal of ultrasonics, ferroelectrics, and frequency control","FirstCategoryId":"1085","ListUrlMain":"https://ieeexplore.ieee.org/document/10879779/","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"","JCRName":"","Score":null,"Total":0}
引用次数: 0
Abstract
In this letter, we proposed a point-to-multipoint fiber-optic time transfer scheme over a star-shaped fiber network based on bidirectional frequency division multiplexing without requiring link calibration. The time signals at the local station and remote stations are encoded into time-varying signals within in different spectral passbands, respectively. The optical carriers with the same wavelength are employed to transfer the two time-varying signals in both directions over a single fiber. The backscattering noises from fiber links can be effectively suppressed by simply electrical filtering due to the non-overlapping on spectrum between the forward and backward time-varying signals. The local station broadcasts the time signal of the reference clock to all remote stations based on space division multiplexing to support point-to-multipoint fiber-optic time transfer. The proposed scheme is demonstrated over a star-shaped fiber network with two remote stations. The results show that the measured mean clock difference can be less than -1.03 ps and 4.99 ps without link calibration, respectively. The measured time stability in terms of time deviation is better than 19.93 ps@1s, 0.50 ps@1000s and 25.35 ps@1s, 0.65 ps@1000s.