High Resolution Frequency Standard Dissemination via Optical Fibre   Metropolitan Network
  We present in this paper results on a new dissemination system of ultra-stable reference signal at 100 MHz on a standard fibre network. The 100 MHz signal is simply transferred by amplitude modulation of an optical carrier. Two different approaches for compensating the noise introduced by the link have been implemented. The limits of the two systems are analyzed and several solution suggested in order to improve the frequency stability and to further extend the distribution distance. Nevertheless, our system is a good tool for the best cold atom fountains comparison between laboratories, up to 100 km, with a relative frequency resolution of 10-14 at one second integration time and 10-17 for one day of measurement. The distribution system may be upgraded to fulfill the stringent distribution requirements for the future optical clocks. 
Francois Narbonneau (SYRTE), Michel Lours (SYRTE), Olivier Lopez   (LPL), Anne Amy-Klein (LPL), Christophe Daussy (LPL), Chr...