Join Modulation Format Identification and OSNR Monitoring Assisted by Intensity and Differential-Phase Features

A joint modulation format identification and OSNR monitoring scheme is proposed. 100% identification accuracies are achieved and maximum mean monitoring errors are respectively 0.19dB, 0.17dB, 0.26dB, 0.40dB, 0.85dB, and 0.64dB for all mainstream formats (PDM-QPSK/-8PSK/-8QAM/-16QAM/-32QAM/-64QAM).