Ultra-wide bandwidth Raman amplifiers

We have discussed the design and noise performance issues for ultra-broadband Raman amplifiers. Superposition may be used to optimise pump wavelengths for flat gain spectra with bandwidths in excess of 100 nm, although numerical simulations are necessary to determine actual pump powers. Shorter wavelength signals suffer greater impairments than those at longer wavelengths due to increased ASE generation as signals approach pump wavelengths, and SRS interactions amongst the signals, and between the pumps.