Fully-Digital Implementation of a Doppler Cancellation Technique for Local Ultra-Stable Frequency Dissemination
Fiber links have proven to be the most robust tools for ultra-stable frequency dissemination over various distance ranges, thanks to an active compensation of the fiber propagation noise [1]. Here, we present our setup for local ultra-stable frequency distribution within an institute, fully based on digital electronics. We use a Red Pitaya SDRlab122 - 16 (RP16) platform to perform a Doppler cancellation scheme, based on a heterodyne Michelson interferometer using a single acousto-optic modulator (AOM) at 110 MHz, in order to cancel the phase noise arising from a 90 m-long fiber link at 1542 nm. The experimental setup is shown in Fig. 1.