100Gbit/s级联交错相位调制码型信号的传输性能

100 Gbit/s transmission performance of serial staggered phase-shift keying modulation formats signal

介绍了一种应用于100Gbit/s传输系统的新型光信号调制码型——交错差分相位调制码(SDPSK)。该码型的解调仅通过一个1bit延时的马赫曾德尔延时干涉仪和一个平衡接收机即可实现。与传统的4种级联相位调制码型进行长距离传输特性比较后证明:基于NRZ码和50%占空比RZ码的SDPSK码与相同包络的DPSK码具有几乎相同的色散容限和一阶偏振模色散容限;与有相同包络的DPSK信号和差分四相相移键控码(DQPSK)信号相比,基于NRZ码和RZ码的SDPSK信号具有更高的抵抗非线性负面效应的能力;经过90km普通单模光纤传输并采用16km色散补偿光纤进行后置色散补偿后,通过带宽值大于125GHz的三阶高斯滤波器检测光信号,RZ-SDPSK信号的接收性能最佳。

A novel staggered differential phase-shift keying （SDPSK） modulation format used for 100 Gbit/s transmission system was proposed. The 2 bit/symbol optical signal could be simply demodulated by using a 1 bit delayed Mach-Zehnder interferometer and a balanced receiver. Compared with the transmission characteristics of the four types of staggered phase modulation formats, such as NRZ-DPSK, RZ-DPSK, NRZ-DQPSK, and RZ-DQPSK formats, it was found that the chromatic and polarization-mode dispersion tolerances of both the SDPSK and DPSK formats with the NRZ and RZ （with 50% duty cycle） shape formats were almost identical, the SDPSK signal could allow larger nonlinear tolerance than the DPSK or DQPSK signal, additionally, the best transmission performance for the RZ-SDPSK signal could be attained if it transmitted through 90 km standard single-mode fiber and 16 km dispersion-compensating fiber, and launched into a third-order Gaussian optical band-pass filter with beyond 125 GHz bandwidth.