PDME enables to control the delay between both polarizations.
The Polarization Division Multiplexing Emulator (PDME) is a device that enables to control the delay between both polarizations. The PDME can be used to emulate Polarization Division Multiplexing (PDM) signal by launching a polarized signal with a given modulation format. At the output of the device, the modulation format will be emulated on both polarizations. For instance, if QPSK is launched at the input, PDM-QPSK will be emulated at the output. The PDME can also be used to emulate Polarization Mode Dispersion (PMD).
Several options are available on the PDME, such as ON/OFF shutter, Variable Optical Attenuator, Variable Optical Delay Line or long free space delay.