Future Prospects for FEC in Fiber-Optic Communications

This paper reviews the application of forward error correction (FEC) techniques to long-haul fiber-optic communication systems. A brief tutorial on error-correcting codes and a discussion of their fundamental limits (on the additive white Gaussian noise channel and on a nonlinear fiber-optic transmission channel) is provided. To illustrate the potential for applying advanced FEC techniques that take channel nonlinearities into account, a novel faster than Nyquist style binary signaling scheme, providing significant rate improvements over a reference benchmark system, is described. To achieve higher spectral efficiencies, the judicious combination of higher order modulation schemes with FEC is discussed. Finally, several potential directions for further research in the application of advanced FEC systems to nonlinear fiber-optic channels are given.