Polarization Control for Continuous Optical Frequency Transfer

SummaryIn this work we present a solution for controlling the polarization state of the signal reaching the remote laser station terminating the optical frequency transfer link (or its section). The proposed controller eliminates the occasional fading of the beat note between the laser and the incoming signal, which is typically observed due to random wandering of the state of polarization of the signal traveling down an optical fiber. The efficiency of the solution is demonstrated for optical frequency transfer via an optical path consisting of real outdoor fibers, as well as fibers on spools and also polarization scramblers speeding up natural polarization fluctuations.