高速光纤通信中的色散问题

光纤中色散问题已成为发展下一代高速长距离光纤传输系统的主要障碍。介绍了色散的概、描述方法；详细讨论了高速光纤通信中的群速度色散和偏振模色散问题，以及当前广泛应用的各种色散补偿技术。     

高速色散控制传输系统中的三阶色散影响

给出了含三阶色散项的强色散控制准线性系统传输方程，分析了三阶色散对该系统的影响特性，并采用数值仿真比较了三阶色散对准线性系统与色散控制孤子系统的影响，指出了三阶色散补偿的必要性和补偿的精度要求。     

光纤光栅偏振模色散研究

对光纤光栅的偏振模色散特性进行了深入的研究，特别是啁啾光纤光栅色散补偿器的偏振模色散。研究表明啁啾光纤光栅色散补偿器的偏振模色散主要由光栅的双折射系数、色散量决定，提出了制作低偏振模色散的色散补偿器的方法。     

动态色散补偿系统中色散监测技术的研究进展

光纤色散是限制光信号传输质量和距离的主要因素之一,动态色散补偿是高速光通信系统中迫切需要解决的问题.色散监测技术是动态色散补偿系统的关键.系统地总结了色散监测技术的研究情况及其进展.对几种动态色散监测技术的机制、特点及其实现进行了分析比较.     

用于高速光传输系统的色散补偿技术

光纤色散是限制光信号传输速率和传输距离的关键因素之一,是目前高速光通信系统中迫切需要解决的问题。本文介绍了色散补偿光纤、啁啾光栅、高阶模色散补偿器以及VIPA等四种色散补偿技术的原理、技术特点以及国内外研究情况,现在不同的色散补偿技术正逐步成熟并走向应用,基于系统的需要,色散补偿器件在向宽带、可调谐方向发展。     

光传输系统中色散补偿问题的探讨

文章通过对光纤色散的产生及其对传输系统影响的介绍,引出了色散补偿技术.在多种色散补偿方法中,侧重探讨了应用比较普遍的色散补偿光纤(DCF)技术,并在此基础上,联系实际工程,具体阐述了光纤色散补偿模块大小在工程中如何计算、如何配备、如何放置等,获得了一些对实际色散补偿系统有参考价值的结论.     

光子晶体光纤的色散特性及其在光通信中的应用

针对光子晶体光纤由于其特殊的几何结构使它具备了很多传统的单模光纤所不具备的奇异的色散特性,如色散可控性、近零超平坦色散、高负色散已及短波反常色散等,讨论了PCF这些色散特性及其在光通信中的应用.     

色散管理孤子的传输特性

论述了色散管理孤子的传输原理,并利用数值方法模拟了色散管理孤子在不同的传输模式中的传输,研究了色散管理孤子特性及其应用。研究结果表明,色散管理孤子具有很明显的周期性,尤其采用平均路径色散为0的模型传输性能更佳。     

色散控制孤子系统的三阶色散分析

对三阶色散在色散控制孤子系统中的特性做了深入分析,采用变分法分析了三阶色散对色散控制孤子的传输特性的影响,给出了各参数的演变特点,并通过数值仿真讨论了三阶色散对系统的演变特点,指出了三阶色散对系统的有害性和补偿的必要性。     

光纤传输系统均衡色散补偿的研究

本文介绍了光纤传输系统中均衡色散补偿的三种主要技术：预Ｃｈｉｒｐ效应脉冲压缩、光栅偶脉冲压缩和Ｆａｂｒｙ－Ｐｅｒｏｔ环型腔脉冲压缩的原理，并对正常色散和反常色散的特性进行了分析。最后，介绍了国际上关干均衡色散补偿研究的最新成果。     

Large PMD Compensated by Four Free Degrees in OTDM System

By introducing a two-stage polarization mode dispersion (PMD) compensator after a optical fiber link with a large PMD,over 270 ps first-order and 2 000 ps2 high-order PMD was compensated. The results show that the two-stage compensator can be used to PMD compensation in the 20 Gb/s optical time division multiplexing system with 60 km high PMD fiber. After compensating, the 270 ps DGD is changed into max. 7 ps. Moreover,the tunable FBG has a function of dispersion compensation.     

Reducing the number of polarization controllers in all-fiber polarization-mode-dispersion emulators using polarization maintaining fiber sub-sections with unequal lengths

Using polarization-maintaining fiber (PMF) sub-sections with unequal lengths, an all-fiber polarization mode dispersion (PMD) emulator with reduced number of polarization controllers is proposed and demonstrated. With six polarization controllers and seven PMF sections, each consists of four sub-sections with unequal lengths and spliced at 45° relative to each other, the generated PMD first- and second-order statistical distributions are close to those of the real fiber link with negligible deviations, therefore, the cost of all-fiber PMD emulators, mainly from the electrically driven polarization controllers, is significantly reduced.     

偏振模色散对波分复用系统性能影响的仿真分析

基于多波长光波在双折射光纤中传输的非线性耦合方程，用分步傅立叶变换求耦合方程的数值解，仿真分析了偏振模色散对波分复用系统脉冲波形的影响，并进一步仿真分析了输入功率、啁啾系数、占空比不同时，偏振模色散对系统性能的影响。     

光纤偏振模散随波长变化特性的研究

目前,偏振模散已经成为高速光纤通信系统发展的主要障碍,本文用琼斯传输矩阵法研究了偏振模散,通过数值模拟给出其统计特性,差分群时延服从麦克斯韦分布;PMD各阶项随波长随机变化;偏振主态在邦加球上的变化走向说明出现了PMD高阶项。     

用波长扫描法测量光纤偏振模色散及其研究

光纤中的偏振模色散ＰＭＤ（Ｐｏｌａｒｉｚａｔｉｏｎ Ｍｏｄｅ Ｄｉｓｐｅｒｓｉｏｎ）是限制高速光纤通信系统传输容量的极限因素，我们首次用波长扫描法在国空实现了对光纤偏振色散的测量；并对国内外多种光纤进行了测量比较，发现国产的光纤质量有待改进。     

Low polarization mode dispersion measurements in ad hoc drawn spun fibers

Polarization mode dispersion causes significant impairment in high bit-rate optical telecommunications systems. It is well accepted that polarization mode dispersion can be strongly reduced by spinning the fiber while drawing, even if a comparison between theoretical predictions and experimental evidence has never been reported. In this paper we focus on the polarization mode dispersion measurement of ad hoc drawn periodically spun fibers, providing a first although preliminary experimental analysis of the spin induced differential group delay reduction. When measuring very low differential group delays as in the case of spun fibers, standard techniques are affected by rather high uncertainties. This problem is usually solved repeating several times the measurements while randomly perturbing the fiber. We support experimentally this method by means of polarization sensitive reflectometric measurements.     

Cluster‐Based Polarized Spectrum Sharing in Channels with Polarization Mode Dispersion

Polarized spectrum sharing (PSS) exploits the spectrum opportunities in a polarized domain. However, when it comes to wideband environments PSS is impaired by the frequency‐dependent polarization mode dispersion (PMD); thus, the effective throughput of PSS drops. To combat the PMD effect, this work proposes a cluster‐based PSS approach to enable PSS on a narrower frequency span. Simulation results show that the effective throughput of PSS on cluster basis outperforms that of PSS on bandwidth and subcarrier basis.     

用光信号偏振度衡量偏振模色散和非线性效应对WDM系统的影响

利用非线性薛定谔方程，计算考虑偏振模色散和非线性效应情况下波分复用（WDM）系统中的RZ码和NRZ码的光信号偏振度，得到DOP随着波长变化的曲线图，同时得到各个信道的眼图。结果表明：通过光信号偏振度的曲线图与眼图的比较，不但明显看出PMD和非线性效应对各个信道的影响是不同的，并且证实偏振度可以作为WDM系统中监测信道性能的监控信号，这将为实现PMD实时最坏信道补偿提供理论依据。     

Novel dispersion compensation method for cross-coupling measurement in PM-PCF based on OCDP

For polarization maintaining photonic crystal fiber (PM-PCF), the cross-coupling measurement can be severely affected by interferogram broadening, due to the large inter-mode chromatic dispersion. In this paper, a novel dispersion compensation method is proposed to mitigate the influence, including a frequency domain algorithm and investigation of the dispersion coefficient for a phase packet in algorithm. A numerical simulation and measurement of birefringence as a function of wavelength reveal that the dispersion coefficient in PM-PCF is much larger than that in PANDA-PM fiber. After compensation, the accuracy of coupling strength measured can be restored and spatial resolution is improved. Experiments show the compensation provides high accuracy with average relative error less than 0.31% and spatial resolution improved 4.1 times.     

偏振模色散模拟器产生二阶PMD的理论研究

对基于保偏光纤（PMF）级联的偏振模色散模拟器（PMD emulator)产生的二阶PMD进行了数值模拟，结果表明，采用偏振控制器（PC）连接明显优于可旋转连接器（FC）连接，当级联段数N＝8时，PC连接的模拟器产生的二阶PMD与理论曲线基本符合；PMF的长度对PMD模拟器模拟二阶PMD并没有明显影响。