The constant growing in traffic demands has driven to look for new methods with which to reduce the occupied bandwidth and efficient use of the optical spectrum. Despite non-orthogonal signalling lead to intersymbolic interference introduction, it can be considered as a promising solution if interference is introduced in a controlled manner. In this paper the modulation scheme called Faster-Than-Nyquist (FTN) is presented for Flexible Passive Optical Networks application. Different ratios of bandwidth reduction vs. power penalty are presented and compared to the Nyquist modulation.

Peer Reviewed