Raman Amplification in the Context of Next-Generation Passive Optical Networks

Next-generation passive optical networks (NGPONs) have the goal of taking even further the transmission distance (up to 100 km) between the communication office and the subscribers near the corresponding Optical network unit (ONU), as well as higher transmission bitrates (10 Gb/s per channel are under study). However, in order to achieve the NGPON goals, the previously PON requirements, namely the passive field implementation, the compliance with the IEEE and ITU-T wavelength allocation plans, and the colourless nature of the ONUs, need to be rethought. With those requirements in mind, Raman amplification for both signal amplification and the use of the remaining power for remote pumping was proposed. Simulations were made in order to test its validity and to judge upon the compatibility with wavelength allocation plans of previously deployed standards, in order to see if this solution is fit for short term upgrade or for satisfying longer term demands.