A comparative analysis of XPM-induced crosstalk resulting from the 9OD coefficient in the presence of GVD in an SCM-WDM optical link

This research investigates the impact of cross phase modulation (XPM) caused crosstalk due to higher order dispersion (HOD) within subcarrier multiplexed-wavelength division multiplexed (SCM–WDM) communication systems across different optical power levels, modulation frequencies and transmission lengths. We carried out an analytical comparison of XPM induced crosstalk due to 9th order dispersion (OD) coefficient using nonlinear Schrödinger equation (NLSE) and couple equations in an SCM–WDM communication links. It is noted that when transmission lengths, optical powers, and modulation frequencies grow, XPM-induced crosstalk has been shown to increase exponentially. Though less significant than 2OD, the effects of 3OD, 4OD, 5OD, 6OD, 7OD, 8OD, and 9OD coefficients are nonetheless present. It can be further noted that the analysis of XPM crosstalk through NLSE is reliable compared to couple equations, as only one approximation method has been utilized to reach the conclusion. Consequently, the results derived from NLSE are definitive and precise. The XPM crosstalk associated with the 9OD parameter ranges from (-550.45 dB to -520.22 dB) when using couple equations, while it fluctuates between (-580.75 dB to -539.21 dB) when employing NLSE as the modulation frequency increases from 0.5 to 10 GHz. Additionally, XPM crosstalk is observed to be between (-540.23 dB to -508 dB) with couple equations, whereas it escalates from (-570.23 dB to -530 dB) when using NLSE as the transmission length extends from 2 to 50 km. Furthermore, XPM crosstalk varies from (-560.23 dB to -528 dB) with couple equations, while it is found within the range of (-590.3 dB to -548.1 dB) using NLSE as the optical power changes from 0.2 to 5mW.