DPSK Error Correction Using Multi-Bit Detection for Enhanced Sensitivity and Compensation of Impairments

We demonstrate a novel multiple-path DPSK detection scheme requiring only a few simple logic gates, This scheme is shown to provide 0.4dB enhancement in back-to-back received sensitivity and 0.85 dB enhancement in the presence of 1 radian of Gordon-Mollenauer nonlinear phase noise. Furthermore, this scheme is shown to provide increased robustness to multiple transmission impairments and transmitter and receiver distortions. We experimentally observe a 2 dB improvement in receiver sensitivity at BER of 1e-3.