Improving dispersion tolerance of manchester coding by incorporating duobinary coding

A Manchester-duobinary coding scheme is proposed to compact the optical spectrum compared with that using pure Manchester coding and thus demonstrate much larger tolerance against fiber dispersion. With this modulation format, the dispersion tolerance can be extended to nearly three times of that using pure Manchester coding. Dispersion tolerance of Manchester-duobinary is from -800 to +920 ps/nm at 2-dB power penalty