Theoretical Analysis on Coherent Noise by Rayleigh Backscattering in Bidirectional Transmission System with Single Mode Fiber

At present, bidirectional transmission over a signal fiber is applied in many filed, such as WDM. Bidirectional transmission reduces the required number of fibers and uses one optical source, so it is lower cost than unidirectional transmission. But coherent noise by Rayleigh backscattering is mainly a factor of degraded system performance in this kind of system. In this paper, the properties of Rayleigh backscattering are analyzed and the model of backscattering transmission is established in single mode fiber. The phase fluctuation is deduced by the autocorrelation function and the power spectral density. In this paper, at the same time, the impact of coherence Rayleigh noise (CRN) on the system performances and the tradeoff between useful signal and CRN are discussed.