Long Haul Single Fiber Reamplified-Reshaped White Rabbit Transmission
Josef Vojtěch, Ondřej Havliš, Martin Šlapák, Vladimír Smotlacha, Tomáš Horváth, Lada Altmannová, Radek Velc, Jan Kundrát, Rudolf Vohnout, Sarbojeet Bhowmick, Michal Hažlinský, Martin Čížek, Jan Hrabina, Lenka Pravdová, Ondřej Čı́p, Jaroslav Roztočil · 2021
Precise time and ultra-stable optical frequency transfers over fiber networks are deployed often in the present days. When size of such infrastructure for precise time and frequency bidirectional transmission is becoming significant, aspects associated with infrastructure operational costs and time needed for deployment of time and frequency transmission must be considered. First can be decreased via fiber sharing with telecommunication traffic, however spectral allocation must be considered carefully to avoid mutual disturbance of time and frequency transmission versus data, and allow future accommodation of growing demands. In the text, we show and discuss alternative spectral bands to be used for time and frequency transmission. Time to deployment can be quite excessive especially when transmission must be established via multiple networks or network domains, also there is a chance of blocking. In case of precise time and optical radio frequency transmission it is possible to use conversion from optical to electrical and back to optical domain with wavelength change. This possibility removes risk of blocking and reduces time to deployment of such services. We also address possibility to change wavelength, or just to extend reach by using simple reamplify and reshape approach.