色散补偿技术在1550nm模拟CATV长途传输系统中应用的研究

色散因素是制约1550nm模拟CATV系统无电中继传输距离的主要因素,本文提出利用已经商用化的色散补偿器件对长距离普通光纤CATV模拟传输系统中的色散进行补偿,并对比了色散补偿光纤和啁啾光纤光栅进行色散补偿的优缺点,同时文章给出了光纤光栅进行色散补偿的最佳位置。模拟系统采用皮长传输,采用啁啾光纤光栅实现对模拟信号的色散补偿可以充分发挥啁啾光纤光栅的低损耗的特性和对单波长进行补偿的特性,本文在国内首次提出采用啁啾光纤光栅（CFG）对1550nmCATV模拟系统长距离光纤传输进行了散补偿,并引用试验证明采用光纤光栅在保证较好载噪比（C／N）和三阶差拍失真（CTB）指标的情况下,能够大幅度地补偿二阶组合失真（CSO）的恶化。     

1550nm长距离传输在巴彦淖尔分公司至所辖各二级分公司传输数字信号的应用

本文提出利用色散补偿器件对长距离G．652光纤进行色散补偿,同时采用喇曼放大器解决1550nm长距离传输中大跨距传输的问题,实现市-县最长182km传输。     

宽带可调谐光纤光栅色散补偿器系统设计

文章提出一种在光纤光栅自身热膨胀效应产生啁啾的基础上,利用铝片热膨胀系数比较高的特点产生应力来增强光纤光栅啁啾,从而实现了宽带、大范围色散调谐的新型光纤光栅色散补偿器。该色散补偿器能够分别对群速度色散及中心波长独立调谐。实验结果表明,在中心波长为1 551.25nm处,能够实现>1.5nm的色散补偿带宽,-350～-690ps/nm的群时延色散调谐范围;在色散为-660ps/nm情况下,能够实现中心波长1nm的偏移。     

宽带色散补偿模块的开发

文章从理论出发设计了一种色散补偿光纤波导结构,并制备出一种高性能的色散补偿光纤.测试结果表明:该色散补偿光纤在1 525～1 625 nm波长范围内具有较大负色散,1 545 nm波长的色散系数为-141 ps/(nm·km).采用该色散补偿光纤成功制备出宽带色散补偿模块.G.652光纤传输链路经过该色散补偿模块的补偿后,C波段的残余色散小于5.0 ps/nm,C波段色散斜率也实现了100%的补偿.     

1550nm长距离传输技术在西双版纳广电模拟CATV传输系统中的应用

色散因素和无电中继距离是制约1550nm模拟CATV系统传输距离的主要因素。本文提出利用已经商用化色散补偿器件对长距离G.652光纤CATV模拟传输系统中的色散进行补偿,改善系统的二阶互调失真,同时采用喇曼放大器成功解决1550nm长距传输中大跨距传输的问题,实现跨越城(乡)间82km大跨距无中继,经过严谨的设计,合理选择发射机的技术参数,精心的调试,成功构建了213km大跨距模拟和数字电视混合传输环网,实现前端的统一。     

1550hm长距离传输技术在西双版纳广电模拟CATV传输系统中的应用

色散因素和无电中继距离是制约1550nm模拟CATV系统传输距离的主要因素。本文提出利用已经商用化色散补偿器件对长距离G．652光纤CATV模拟传输系统中的色散进行补偿，改善系统的二阶互调失真，同时采用喇曼放大器成功解决1550nm长距传输中大跨距传输的问题，实现跨越城（乡）间82km大跨距无中继，经过严谨的设计，合理选择发射机的技术参数，精心的调试，成功构建了213km大跨距模拟和数字电视混合传输环网，实现前端的统一。     

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。     

利用光子晶体光纤实现10 Gb/s光传输系统的色散补偿

利用光子晶体光纤（PCF）在10Gb/s光传输系统中对普通单模光纤中传输的光脉冲进行了色散补偿，获得了很好的补偿效果。实验中，10Gb／s光脉冲序列经过2.163km普通单模光纤被展宽后．利用26m长光子晶体光纤对其进行色散补偿．补偿后脉冲基本恢复到了初始形状。进一步的理论计算表明，此光纤在C波段20nm波长范围内对普通单模光纤能够实现较好的色散斜率补偿，补偿后剩余色散小于5ps／nm。理论与实验结果表明光子晶体光纤在色散补偿方面具有很大的潜力．在未来光通信系统中将发挥重要作用。     

10 Gbit/s无中继光传输系统的色散补偿

在光纤通信中色散补偿的方式有很多,文章分别研究了色散补偿光纤(DCF)、啁啾光纤光栅(CFG)两种色散补偿方案.通过数值仿真分别实现了10 Gbit/s 198 km和220 km G.652光纤的无中继传输.仿真实验证实,采用CFG补偿可使传输距离增加约10%,并且当误码率为10-12时,无误码传输的功率代价仅为1.6 dB.     

基于高非线性光纤动态宽带色散补偿传输系统的性能分析

分析了采用高非线性光纤的动态宽带色散补偿器（DDCD）的组成和工作原理,对其色散补偿效果进行了数值分析,仿真结果表明,这种器件的动态宽带色散补偿效果明显,动态补偿的范围可达145ps/nm,对DDCD的组成方案提出了改进措施,进一步完善了其功能。     

Tunable dispersion compensator based on a fiber Bragg grating written in a tapered fiber

We report a novel dispersion tunable device for first-order dispersion compensation. It is based on a fiber Bragg grating written in a tapered fiber with a specific profile. The taper profile allows tuning the dispersion of the grating by stretching the fiber while the linearity of the group delay is preserved. A device with 0.8 nm of useful bandwidth and dispersion value tunable over more than 400 ps/nm is reported.     

Fiber Bragg grating fabrication for dispersion slope compensation

Group-delay dispersion slope causes signal deterioration in long-distance high-data-rate communication systems. We report the fabrication of high-quality apodized and chirped fiber gratings with dispersion slopes as high as -1800 ps/nm/sup -2/ over a 0.7-mn bandwidth-sufficient to compensate for the dispersion slope of >25000-km length of standard fiber at a wavelength of 1550 nm. We believe this is the first time that fiber Bragg gratings have been specifically designed and fabricated for dispersion slope compensation. The fabrication technique uses a standard unchirped phase mask and two scans of the inscribing UV beam.     

Waveform degradation due to dispersion effects in an optical CPFSKsystem

Waveform degradation due to polarization and chromatic dispersions in a single-mode fiber is calculated for a coherent CPFSK signal. For a single-mode fiber with polarization dispersion of ⩽1 ps, chromatic dispersion almost dominates the system. However, if a fiber has polarization dispersion of more than a few picoseconds and a chromatic dispersion of less than 0.1 ps/km/nm, which can be attained by using a dispersion-shifted fiber and/or by electric dispersion compensation, polarization dispersion will restrict transmission capacity. For instance, polarization dispersion of 5 ps will restrict a bit rate by ~60 Gb/s when chromatic dispersion is fully reduced using a dispersion-shifted fiber or applying electrical equalization     

12300 ps/nm, 2.4 Gb/s nonregenerative optical fiber transmissionexperiment and effect of transmitter phase noise

A nonregenerative optical transmission experiment with a chromatic dispersion of more than 10000 ps/nm is reported. Externally intensity-modulated 2.4 Gb/s optical signals were transmitted over 710 km of nondispersion-shifted optical fiber using ten Er-doped fiber amplifiers with a total net optical gain of 125 dB. Although the total chromatic dispersion amounted to 12300 ps/nm, the power penalty observed was as small as 0.5 dB, and an error floor was not observed. The effect of transmitter phase noise associated with fiber chromatic dispersion was experimentally investigated     

Improved supercontinuum generation through UV processing of highly nonlinear fibers

We demonstrate that UV exposure of highly nonlinear, germano-silicate fibers can significantly broaden the infrared supercontinuum generated by femtosecond pulses in these fibers. Both simulations and measurements of the fiber chromatic dispersion show that UV-induced refractive index changes increase the waveguide dispersion by up to 5 ps/(nm-km) at 1570 nm and shift the dispersion zero by over 100 nm. We examine fibers with a range of UV exposure levels and show that the short wavelength edge of the supercontinuum can be continuously changed by more than 100 nm. We also show that the long wavelength edge is extended beyond that of the unexposed fiber. The resulting continuum spans from 0.85 to 2.6 /spl mu/m. Cutback measurements show that the supercontinuum in the exposed fiber is generated in as little as 1 cm of fiber. A nonlinear Schro/spl uml/dinger equation (NLSE) model of the supercontinuum generation in the nonlinear fiber shows that the short wavelength behavior of the continuum is primarily controlled by changes in the fiber dispersion caused by the UV-induced change in refractive index of the fiber core.     

A novel design for dispersion compensating photonic crystal fiber Raman amplifier

This letter presents a novel design for dispersion compensating photonic crystal fiber (DCPCF) which shows inherently flattened high Raman gain of 19 dB (/spl plusmn/1.2-dB gain ripple) over 30-nm bandwidth. The proposed design module has been simulated through an efficient full-vectorial finite element method. The designed DCPCF has a high negative dispersion coefficient (-200 to -250 ps/nm/km) over C-band wavelength (1530-1568 nm). The proposed fiber module of 5.2-km length not only compensates the accumulated dispersion in conventional single-mode fiber (SMF-28) but also compensates for the dispersion slope. Hence, the designed DCPCF module acts as the gain-flattened Raman amplifier and dispersion compensator.     

Dynamic dispersion compensation in a 10-Gb/s optical system using anovel voltage tuned nonlinearly chirped fiber Bragg grating

We experimentally demonstrate dynamic dispersion compensation using a novel nonlinearly chirped fiber Bragg grating in a 10-Gb/s system. A single piezoelectric transducer continuously tunes the induced dispersion from 300 to 1000 ps/nm. The system achieves a bit-error rate=10^-9 after both 50 and 104 km of single-mode fiber by dynamically tuning the dispersion of the grating between 500 and 1000 ps/nm, respectively. The power penalty after 104 km is reduced from 3.5 to <1 dB     

Investigations on the dominant dispersion penalties occurring inmultigigabit direct detection systems

The dominant penalties are wavelength chirp, line broadening due to optical back reflection, and mode partition noise due to insufficient side-mode suppression. Experimental results on pulse compression at 1550 nm and on penalty reduction by dispersion compensation are presented. The dispersion compensation is achieved by adding a negative dispersive fiber link to a standard fiber link with positive dispersion at 1550 nm. In this way it was possible to transmit 5 Gb/s over a 111-km fiber link