| 摘要 |
<p>A transmitter terminal in an ultra-long haul optical transmission system receives separate channel input signals in separate ones of a plurality of return-to-zero transmitters (RZTX). Each RZTX generates a corresponding forward error correction (FEC) modulated output signal in a separate channel frequency sub-band including predetermined channel separations from adjacent channel frequency bands. A multiplexing arrangement multiplexes the plurality of channel frequency bands from the RZTXs into separate groups of frequency bands. The groups of frequency bands have predetermined band-gap separations therebetween, and each group of frequency bands has a predetermined separate pre-chirp introduced therein before being multiplexed with all other groups of frequency bands into a single multiplexed output signal. An optical transmission line (OTL) is subdivided into predetermined sections and receives the single multiplexed output signal. A separate Raman amplifier (RA) is located in each separate section of the OTL for providing backward distributed Raman amplification. A dispersion compensating line amplifier (DCLA) is located in predetermined space-apart sections of the OTL for introducing dispersion compensation for the single multiplexed output signal and each of the groups of frequency bands therein. <IMAGE></p> |
