Non-Orthogonal Multiple Access for Long-Haul Elastic Optical Networks

We investigate a method of power-domain non-orthogonal multiple access (NOMA) as a promising technique for flexible, spectrally efficient wavelength assignment in long-haul elastic optical networks. The proposed method allows the full overlap of multiple independent and unsynchronised optical signals on the same wavelength, where different signals are allocated different power levels. The signals are separated using the method of successive-interference-cancellation (SIC) at the receiver. The performance of optical NOMA with and without rate adaptation is evaluated in this paper, in the presence of chromatic dispersion and carrier frequency offset.