2019 Volume E102.B Issue 5 Pages 1005-1009
The efficiency of generating four-wave mixing (FWM) from phase-modulated (PM) optical signal is studied. An analysis, that takes bit shifts occurring during fiber propagation due to group velocity differences into account, indicates that the FWM efficiency from PM signals is smaller than that from continuous waves in fiber transmission lines whose distance is longer than the walk-off length between transmitted optical signals.