Experimental demonstration of robustness and accuracy of an MZI-based OSNR monitor under transmitter drift and reconfigurable networking conditions for pol-muxed 25-Gbaud QPSK and 16-QAM channels

We experimentally demonstrate the robustness of an MZI-based OSNR monitor under reconfigurable network and transmitter drift. The monitor calibration factors for 25 Gbaud PM-QPSK signal are stored after assembly and applied to study the accuracy of the OSNR monitoring unit when different changing scenarios outside the monitor occurred.