偏振模色散仿真与抑制方法研究

【作者】 邸金红；

【导师】 禹延光；

【作者基本信息】 郑州大学 ， 通信与信息系统， 2004， 硕士

【摘要】 由于光放大器和各种色散补偿技术的采用，光纤损耗和色散对系统的传输距离不再起主要限制作用。研究表明，当传输速率达到10Gbit／s以上时，原本微小的偏振效应——偏振模色散(Polarization mode dispersion，PMD)明显损害系统的传输性能，限制系统的传输距离。因此偏振模色散成为目前国际上光纤通信领域研究的热点之一。 偏振模色散是由于光纤结构的不完美性以及外界应力作用而产生的，是一个服从麦克斯韦分布的随机量。本文围绕光纤中的偏振模色散这一重要效应展开研究。首先分析了偏振模色散的起因、描述模型以及对通信系统的影响。以推导出的耦合非线性薛定谔方程为理论模型，采用分步傅立叶变换对偏振模色散进行了数值仿真。改变脉冲的各种参数，对脉冲在考虑偏振模效应的光纤系统的传输进行了仿真，并分析了仿真结果。仿真分析了偏振模色散对不同码型系统的影响，得出了一些有意义的结论。采用色散补偿光纤进行色散补偿之后，色散补偿链路的选取和传输码型、入射功率等都有关系，通过仿真得出，要得到好的系统性能，就要综合考虑这些因素。最后对偏振模色散抑制方法进行了研究。比较分析了几种抑制方法，及补偿技术中几种常用的反馈控制方案和前馈控制方案。更多还原

【Abstract】 Fiber loss and dispersion have been overcome greatly because of the development of optical amplifiers and chromatic dispersion compensation technology. When the transmission bit-rate can get to 10 Gbit/s and above, research show that Polarization Mode Dispersion (PMD) ignored formerly can damage the performance of system and limit the transmission bit-rate and length of system. So PMD turns into the focus of research of Optical Fiber Communication system in the world.PMD in fiber is formed for the incomplete structure and the action of external stress on optical fiber and is a stochastic variable. This paper formulates the PMD generally. At first the theories on PMD are analyzed involving the origination and model of PMD. The influence of PMD on optical fiber communication system is also described. The coupled nonlinear Schrodinger equation is solved by means of split-step Fourier transform, and the influence of PMD on transmission system is numerically calculated by changing parameters of pulse. The several simulation results are analyzed in detail. The influence of PMD on different data-formats system is simulated and some significative results are gained. The performance of dispersion compensation transmission system is associated with data-formats and power of incidence. Several factors must be considered by numerically calculating if a better system performance is obtained. Finally techniques of restraining PMD are studied. Several adaptive feedback controlling techniques and feedforward controlling techniques in PMD compensation systems are also described in detail.更多还原