【摘 要】
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In BeiDou ground-based navigation signal net,the technology of optical fiber time and frequency transfer,whose design precision excels 0.5ns,is used to realize the time synchronization between ground
【机 构】
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Beijing Satellite Navigation Center, Beijing, 100094, China
论文部分内容阅读
In BeiDou ground-based navigation signal net,the technology of optical fiber time and frequency transfer,whose design precision excels 0.5ns,is used to realize the time synchronization between ground stations.Limited by condition and precision,some techniques such as TWSTFT and satellite common-view are not suitable for optical fiber time synchronization testing.In this paper,the clock travel method based on Cesium Clock with high-precision is used to test the per-formance of optical fiber time synchronization,and its handling process is discussed in detail.At the same time,the main error sources are analyzed in the paper.The closed loop result of outfield testing excels 0.4ns,which validates the feasibility of the method.Meanwhile,unilateral delay of optical fiber device is ca-librated,and time delay of 100ns level is detected,which is important for system data processing.
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