Optimizing clock enhancement to achieve modulation-format-independent all-optical clock recovery

We investigate a clock enhancement technique with signal pre-distortion using a semiconductor optical amplifier based Mach-Zehnder interferometer (SOA-MZI). Working together with a Fabry-Perot filter (FPF) based all-optical clock recovery module, this technique achieved modulation-format-independent all-optical clock recovery with a simple and straight-forward configuration. We then analyze the clock enhancement technique with numerical simulations. The simulations determine the optimal operation points of the SOA-MZI for RZ and NRZ inputs and demonstrate effective clock amplitude improvement and clock amplitude fluctuation reduction.