Investigation of 20Gb/s WDM-PON transmission over 40-km employing 16QAM signal with blind equalization

We apply 16QAM into the downstream modulation in long reach WDM-PON and utilize blind equalization at the ONU receiver to improve the system performance. Simulation results indicate that, with the blind equalization, after transmission over 40-km single mode fiber (SMF) at the speed of 20Gb/s, BER is remained below 10 -3 at -17.2dBm receive sensibility. The results also show that the blind equalization is able to suppress the crosstalk between two adjacent WDM channels spacing 25GHz and thus improve the constellation phase rotation.