Simultaneous transmission of accurate time and stable frequency through bidirectional channel over telecommunication infrastructure with excessive spans

摘要

In this paper, we present simultaneous transmission of accurate time and stable frequency over 306 km long fiber link. The fiber link belongs to the Time and Frequency infrastructure which is being gradually developed and shares fiber footprint with data network. The link had been originally deployed with wavelength division multiplexing systems for C and L band systems. But it has been recently upgraded to support 800 GHz wide super-channel with single signal path for both directions. This bidirectional super-channel spans over two extensive segments with attenuation of 28 and 25 dB.