Direct Measurement of Vector Polarization-Mode Dispersion From Repeated Random Data by Use of Linear Optical Sampling

Polarization-dependent optical sampling techniques measure the complex electric field, allowing one to monitor the degrading effects of a communication channel. Here we show the ability to extract the polarization-mode dispersion of the transmission channel from a remote measurement of transmitted repeated 10-Gb/s differential phase-shift keying modulated data. This approach is independent of modulation format and data rate. We demonstrate results both with and without referencing to the laser phase. We achieve a differential group delay resolution of 0.2 ps for an unreferenced measurement.