Monitoring of Linear and Nonlinear Signal Distortion in Coherent Optical OFDM Transmission

Transparent optical networks are in the interest of network operators for many years. To operate such networks efficiently and reliably has been identified as a difficult task, since there is no access to a strict performance parameter like the bit error ratio in the optical path. In particular the signal degradation from the fiber nonlinearity accumulates during propagation along the optical transmission line and can only be fully characterized at the final destination. On the other hand recent improvement in receiver technology allows to introduce complex signal processing at the receive side. In this contribution a concept is described to separate linear and nonlinear signal distortions, in order to tune the per channel power in meshed WDM networks. The method furthermore enables the estimation of the associated achievable spectral efficiency.