Improved FWM model for coherent optical OFDM systems taking into account dispersion compensation

A simplified closed-form expression for the Four Wave Mixing crosstalk is derived. Four Wave Mixing is one of the main sources of performance degradation in coherent optical OFDM systems. This expression is in very good agreement with the exact model over a wide range of system parameters outperforming the previously published model. This model is both simple and at the same time a reliable tool that can be used to calculate the performance of systems employing CO-OFDM and/or can be also used as an integral part of physical layer aware algorithms. Furthermore, unlike the previously published model, this model is also expanded in systems employing DCF for dispersion compensation.