Electronic mitigation of fiber transmission impairment

Dispersion and nonlinear wave impairment upon transition over single channel optical fiber are reviewed. Since chromatic dispersion can be predicted, transmit techniques are developed to contain its effects on digital signal transition. Advancements in these techniques are given high-lighting dispersion resilience versus electronic predistortion. The latter can also handle self phase modulation due to Kerr effect. Technologies for constant-envelope modulation formats are also considered for its resilience to nonlinear impairments. On the other hand, receiver techniques have drawn much attenuation in the last few years. Advanced receiver techniques are outlined. Optical equalization is given as a reference to its electronic version. Both analog and digital control strategies are considered. Feed forward and compensation-feedback equalization are outlined. The optimum receiver minimizes the error probability by selecting the most likely sequence. This is done by maximum likelihood sequence estimation (MLSE) Viterbi-like receiver with symbol rate sampling, preceded by a matched filter.