Polarization Independent All-Optical 3R Regeneration Based on the Kerr Effect in Highly Nonlinear Fiber and Offset Spectral Slicing

A detailed experimental characterization of a polarization-independent all-optical 3R regenerator is presented. The regenerator is comprised of a self-pulsating distributed feedback laser for clock recovery, cross-phase modulation in a highly nonlinear fiber (HNLF) and offset spectral slicing for retiming, and self-phase modulation in an HNLF and offset spectral slicing for reshaping. A key feature of the regenerator is that polarization-independent operation is achieved without additional complexity as compared to a conventional polarization-dependent implementation. The regenerator performance is assessed for important properties of the input signal, including the optical signal-to-noise ratio, waveform distortion due to residual group velocity dispersion and polarization mode dispersion, state-of-polarization, power, and wavelength. With careful attention to key design parameters, excellent performance is achieved.