【出 处】Management Information and Optoelectronic Engineering: Proceedings of the 2015 International Conference on Management, Information and Communication & Proceedings of the 2015 International Conference on Optics and Electronics Engineering
【摘 要】 In this paper, we propose and demonstrate a method for optical signal to noise ratio (OSNR) monitoring of 40 Gbit/s return-to-zero differential quadrature phase shift keying (RZ-DQPSK) signal based on half symbol delay-tap sampling with optimal polyn... 更多 >> In this paper, we propose and demonstrate a method for optical signal to noise ratio (OSNR) monitoring of 40 Gbit/s return-to-zero differential quadrature phase shift keying (RZ-DQPSK) signal based on half symbol delay-tap sampling with optimal polynomial fitting. At first, we present the operation of half symbol delay-tap sampling with polynomial fitting. By searching the most appropriate sampling domain in 2-dimensional asynchronous sampling plots, it ensures that the estimation OSNR is the closest to actual value. Then to investigate the performance of the proposed method, numerical simulations are performed on a 40 Gbit/s RZ-DQPSK simulation system with a certain range of chromatic dispersion (CD) and polarization mode dispersion (PMD). The results show that the OSNR is accurately monitored in the wide range 10 dB to 30 dB without CD and PMD, and the maximum absolute measuring error is down to 0.0448 dB. Moreover, the proposed OSNR monitor method is robust to transmission impairments, estimation error is kept within 1 dB under low OSNR value when CD and PMD are up to 50 ps/nm and 12 ps respectively. << 收起
