Towards sub-nanosecond synchronization of a telecom network by fiber optic distribution of UTC(k)

The operation of a mobile telecom network relies directly on the synchronization of thousands of base stations that must be robust and operate reliably 24 hours a day. Nowadays networks using advanced Long Time Evolution (LTE) standard need not only frequency syntonization, but also time synchronization that should ideally be traceable to UTC. In this work we present first results of providing UTC(PTB) (1 PPS and 10 MHz) by optical fiber to a test center of Deutsche Telekom in Bremen. The work aimed at a proof-of-concept in real telecommunication environment and the demonstration of the long-term operation capability and scalability of the approach. A potential future application is the comparison of UTC(PTB) and UTC(DTAG).