Exploring Capacity Limits of Fibre-Optic Communication Systems

Advanced technologies such as distributed Raman amplification with cascaded pumping, advanced modulation formats, and coherent detection with digital signal processing are being developed to increase the capacity and reach of fibre-optic communication systems. The question then arises whether fundamental limits exist that prevent increasing fibre capacity while maintaining an attractive system reach despite the best advances in technologies. This paper reviews an approach to provide a lower bound of such limits, largely independent of restrictive assumptions.