Phase noise in a bidirectional transmission system with polarization maintaining fiber

At present, bidirectional transmission over a signal fiber is applied in many fields, such as WDM. Bidirectional transmission over a signal fiber can reduce the required number of fibers and uses one optical source, so it is lower cost than unidirectional transmission counterparts. In this paper, the phase-noise counteracting characteristic in the bidirectional transmission over a polarization maintaining fiber (PMF) due to different polarization rotating angle of counter-propagation light is analyzed. The analyzing results indicate that the bidirectional system with a special polarization rotating angle of counter- propagation light has a good property that can counteract phase noises coming from external factors such as temperature etc. reciprocal factors. Thus, phases' fluctuation can be reduced and it has the advantages of measuring phase change and achieving phase calibration. Based on the result, using Jones matrix, the established system is discussed and the phase difference owing to nonreciprocal parameters such as Faraday electromagnetic induction is obtained. So the calibration of phase is achieved according to the measured results.