CD and PMD monitoring based on RF spectrum analysis with optical filtering

Chromatic dispersion (CD) and polarization mode dispersion (PMD) monitoring methods based on RF spectrum analysis are demonstrated experimentally. By using a narrow band FBG notch filter, centered at optical carrier/10GHz away from carrier, corresponding RF power ratio/power can be used as CD/PMD monitoring signal in high-speed optical communication systems such as 57-Gbit/s D8PSK.