Stimulated Raman crosstalk in multi-pumped DRA

Closed-form formulae have been analytically derived to estimate crosstalk due to stimulated Raman scattering (SRS) in wavelength division multiplexed distributed Raman amplifier (DRA). The derived formulae are applied to study the crosstalk performance of multi-pumped DRA with forward and backward pumping configurations. Based on the calculation, it is reported that backward pumping configuration that is preferred to other configuration has the worst crosstalk performance due to SRS. The result assumes importance because backward pumped DRA exhibits best gain performance. Performance of DRA for other parameters such as wavelength separation and input power is also investigated.