Spatially resolved chromatic dispersion measurement by a bidirectional OTDR technique

In this paper, a technique for spatially resolved chromatic dispersion meas urement of installed optical fiber links is presented. The method is based on the analysis of bidirectional optical time-division reflectometer (OTDR) traces at different wavelengths obtained by a specifically designed tunabl e external source. Measurement accuracy is improved through a particular al gorithm that corrects the OTDR nonlinearity error. Experimental data on spa tially resolved chromatic dispersion of installed dispersion-shifted and no nzero-dispersion fibers are reported.