Delivering 10 Gb/s optical data with picosecond timing accuracy over 75 km distance

The transfer qf very accurate time information over long distances has numerous applications in modern society. Satellite-based links have typically been used so far, but fiber-optical signals can transfer time with increased precision. In this paper, a novel method suited for time transfer employing conventional optical data signals is demonstrated; spec~fically, transmission of 10 Gb/s signals for up to 75 km over an amplified bidirectional link enabling time transfer with 4 ps accuracy is shown. The vety high accuracy achieved and compatibility with existing optical links may allow reliable synchronization of vital infrastructure, and positioning systems with mm-level precision