Statistics of accumulated splice-cross talk in weakly coupled few-mode fiber links

Abstract

Abstract For uncoupled mode-division-multiplexed systems in weakly coupled (WC) few-mode fibers (FMFs),we numerically investigate the effect of splices on the statistical regularities of WC property preservation alongthe transmission link. At each splice, the probability density functions of intermodal cross talk (XT) for thetransmittedlinearlypolarizedmode(s)arenumericallyanalyzedbyusingGaussianfitting.Undertheassessmentcriterion of accumulated intermodal XT affected by discrete splices, we give an empirical evaluation on theuncoupled probability value versus transmission distance, for WC FMF links with different splicing qualities. © 2016 Society of Photo-Optical Instrumentation Engineers (SPIE) [DOI: 10.1117/1.OE.55.7.076118] Keywords: few-mode fibers; mode cross talk; mode-division multiplexing; fiber optics communications.Paper 160703 received May 7, 2016; accepted for publication Jul. 12, 2016; published online Jul. 28, 2016. 1 IntroductionFew-mode fibers (FMF) systems have been considered as apromising solution to overcome the fundamental capacitylimit of single-mode (SM) systems. In an FMF system, inwhich the separation between nondegenerate linearly polarized(LP) modes is preserved [i.e., to use the weakly coupled (WC)approach aimed at minimizing distributed mode coupling],each LP mode(s) can be separately detected using simple 2×2 (nondegenerate LP