Fiber nonlinearity suppression in fiber-optic transmission systems using an optical quadratic phase pre-compensation method

In this paper, we propose, simulate and experimentally demonstrate a convenient pre-compensation method, which is capable of mitigating fiber nonlinearity in dense wavelength-division-multiplexed long-haul high-speed systems. From nonlinear Schrodinger equation, we deduce that an optical signal with quadratic phase will have better nonlinear suppression ability than other phase pre-compensation methods. In our pre-compensation method, before being launched into fiber, each transmitted wavelength is modulated by a phase modulator, which is driven by a periodic parabolic electric driving signal. Thus, each channel will have a quadratic phase. Both of the simulations and experimental results show that the fiber Kerr nonlinearity can be reduced effectively and the BER can be improved by two orders of magnitude.