Effect of dispersion compensation schemes on nonlinear phase noise in optical transmission system

The formulas for calculating nonlinear phase noise are proposed for both pre-compensation and post-compensation schemes. Based on these formulas, the phase noise, power tolerance and optimal signal peak power of both dispersion compensation schemes are analyzed and discussed in detail, respectively. The result shows that pre-compensation is more effective in reducing the nonlinear phase noise when compared with post-compensation. Its suppression ability improves with signal energy, ASE power spectral density and transmission distance increasing. The pre-compensation system possesses higher power tolerance than post-compensation system and the optimal signal power is increased when dispersion is taken into account, which results that the optimal phase shift is larger than 1rad. And the optimal signal power for pre-compensation system is larger than post-compensation system.