CD-insensitive PMD monitoring using electronic domain orthogonal coherent processing for OOK optical link at 40 Gbits/s

Abstract

We theoretically and experimentally demonstrated the polarization mode dispersion (PMD) monitoring of 40Gbit/s NRZ and RZ links by using a electronic domain orthogonal coherent technique; this method can detect the spectrum phase difference between the fast axes and slow axes. In my experiments, the radio frequency (RF) of local oscillator (LO) is set to 5GHz, the monitoring range is around 0–100 ps, the maximum fluctuation range of measured phase difference is better than 0.05rad for 40Gbit/s NRZ link. This method is independent on data rate for intensity modulation direct detection (IM/DD) links.