Dispersion analysis of fiber Raman amplifier for WDM system

• Fiber Raman amplifiers shows cross phase modulation for mutichannels.
• Fiber Raman amplifiers parameters responsible for XPM.
• FRA XPM varies with channels spacing among WDM.

We have analyzed the effect of dispersion in fiber Raman amplifier (FRA) by propagating two channels together through the same backward pumped Raman fiber. We have investigated the quality factor and gain for different values of dispersion up to third order. The optimum value of second and third order dispersion has been evaluated for different channel spacing. It is observed that for a channel spacing of 50 GHz, the optimum value of dispersion (D) for a 10 km Raman fiber is 2 ps/nm/km and second order dispersion β2 is −2.551 ps2/km. The third order dispersion parameter β3 is also analyzed for different channel spacing from 50 GHz to 20 GHz and we have obtained its optimum value as −0.10967 ps3/km for both 50 GHz and 25 GHz, whereas for channel spacing of 20 GHz, the optimum value of β3 comes out to be −0.1469 ps3/km.