Accuracy of two-way time transfer via a single coaxial cable

作者：Panek Petr^*; Kodet Jan; Prochazka Ivan

来源：Metrologia, 2013, 50(1): 60-65.

DOI：10.1088/0026-1394/50/1/60

In order to find limits of the accuracy of the two-way time transfer (TWTT) via a single coaxial cable, we have carried out a detailed analysis which is presented in this paper. We applied the TWTT concept when a transmission line is driven by pulse current drivers and the times of arrival of the pulses are measured at the ends of the line. In addition to the estimation of the accuracy, the analysis provides several rules for proper design of a TWTT system with optimal performance. Based on this concept, a TWTT system for highly accurate time distribution or comparison has been designed and realized. For distances up to 1 km the accuracy was better than 100 ps without any additional correction or adjustment. After the influence of the non-symmetry of input-output circuits was corrected, the errors were lower than 20 ps for distances up to 2 km. The TWTT system is designated for keeping unified time in a net of event timers distributed in one building or in a relatively small area. The timing units forming the system guarantee the time transfer parallel to the time tagging of external pulses.

• 出版日期2013-2