OPTICAL TRANSMISSION SYSTEM WITH REDUCED KERR EFFECT NONLINEARITIES

摘要

An optical transmission system is formed to include an optical phaseconjugator at alternate repeater sites to minimize the presence of four-wavemixingand other Kerr effect nonlinearities in systems using optical fibertransmission paths(particularly in systems using DWDM and launching relatively high powersignalsinto the low dispersion fiber). Raman gain is included in each fiber span (orinalternate fiber spans) so as to provide a "negative absorption" along thelength of thefiber and thereby provide for essentially symmetrical power distribution alongthelength of each span, where the presence of such a symmetric power distributiononeach side of an optical phase conjugator has been found to significantlyimprove itsperformance.