Investigation of Phase Noise Compensation Methods for 43 Gbit/s RZ-DQPSK Multi-Span Transmission with Direct Detection

Inhalt:
This paper investigates the performance of different phase noise compensation options for a 43 Gbit/s RZDQPSK multi-span transmission system with distributed inline under-compensation and direct detection. The efficiency of different phase noise compensation methods, namely (i) the compensation of the mean nonlinear phase shift (MEAN), (ii) the multi-symbol phase estimation (MSPE) and (iii) the combination of both methods is examined by Monte-Carlo simulations for varying pre- and post-compensation. Furthermore, the performance of these three strategies for different average fibre input powers is investigated. Not only the optimum phase noise compensation strategy is identified, also the impact of the dispersion map is considered and compared to the conventional receiver. For the best noise tolerant receiver option a maximum Q-gain of up to 2.7 dB can be achieved for a wide range of values for the fibre input power.