Reducing interchannel crosstalk in long-haul DWDM systems

摘要

Nonlinear interaction between signal channels may result innsignificant performance degradation in transoceanic densenwavelength-division-multiplexing (WDM) transmission systems operated atnhigh bit rates. In this paper, we report that the nonlinear crosstalknfor systems with high spectral efficiency can be suppressed if WDMnchannels are launched with orthogonal relative states of polarization.nIt is shown that for adjacent channels (that experience the strongestnnonlinear interaction) the launched relative state of polarization isnmaintained over the large distance of low polarization-mode dispersionnfiber typically used in undersea systems. Numerical studies, as well asnexperimental results, are presented for standard and dispersionnslope-matched dispersion maps