共查询到20条相似文献,搜索用时 46 毫秒
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色散管理是在波分复用系统中, 周期地使用色散符号相反的光纤,使总的路径平均色散系数接近于零,系统中的色散就得到了补偿的一种技术.研究了波分复用集总放大色散管理系统中交叉相位调制的不稳定性,解析和数值研究表明,当路经平均色散系数表现为反常色散时,存在多阶边带;当路经平均色散系数表现为正常色散时,解析研究表明只存在最低阶边带,数值模拟显示噪声谱中最低阶边带噪声谱功率最强,解析和数值研究得到的结论一致.
关键词:
色散管理
波分复用
边带不稳定性 相似文献
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研制了一种适用于平行板传输连接的平面火花隙三电极开关,开关正负电极为半圆形状,触发电极为细条状。将之替代立体式(半球形电极)火花隙三电极开关并应用于爆炸箔起爆装置中,装置回路参数将得以优化。实验测试了空气间隙为4.12, 3.14和2.2 mm的平面火花隙三电极开关的性能。结果表明,在开关间隙间距一定的情况下,随着电压的升高,开关间隙的放电时延和分散时间呈指数降低,开关电感小于15 nH;对于不同范围内的应用电压,使用不同间隙间距的开关,其分散时间不大于10 ns。该开关应用于较低充电电压(小于10 kV)的脉冲功率装置中,与立体式火花隙三电极开关相比,回路电感降低了约50 nH,放电周期缩短近1/3,峰值电流增加约1/3。 相似文献
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We propose a technique for chromatic dispersion monitoring based on optical time domain level monitoring.Experimental and simulation results show that the technique is effective for the monitoring of dispersion in 42.7-Gbps CS-RZ signals for dynamic dispersion compensation. 相似文献
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We present a modified method to design photonic crystal fibers with flattened dispersion characteristics. By replacing the circular air-holes of the first central ring with elliptic air-holes, we observe a more flattened dispersion curve. Plane-wave expansion (PWE) method is used to analyze the dispersion property in a high-index core PCF. The simulation results are presented, and ultra-low and ultra-flattened dispersion curves over wide wavelength range are demonstrated. 相似文献
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《中国光学快报(英文版)》2017,(3)
The common and traditional method for optical dispersion compensation is concatenating the transmitting optical fiber by a compensating optical fiber having a high-negative dispersion coefficient.In this Letter,we take the opposite direction and show how an optical fiber with a high-positive dispersion coefficient is used for dispersion compensation.Our optical dispersion compensating structure is the optical implementation of an iterative algorithm in signal processing.The proposed dispersion compensating system is constructed by cascading a number of compensating sub-systems,and its compensation capability is improved by increasing the number of embedded sub-systems.We also show that the compensation capability is a trade-off between the transmission length and bandwidth.We use the simulation results to validate the performance of the introduced dispersion compensating module.Photonic crystal fibers with high-positive dispersion coefficients can be used for constructing the proposed optical dispersion compensating module. 相似文献
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偏振复用光纤通信系统色散均衡器及算法的研究 总被引:2,自引:0,他引:2
设计了一种适用于偏振复用相干解调光纤通信系统的色散均衡器,用于补偿信道传输的色散损伤。该均衡器采用半码元间隔的蝶形有限脉冲响应滤波器结构,与此结构配合的自适应算法分别采用最小均方算法和递归最小二乘算法。通过仿真实验,分析了两种算法对残留色度色散和偏振模色散的补偿容限。仿真结果表明,递归最小二乘算法的补偿效果优于最小均方算法,它可以同时补偿1760ps/nm的残留色度色散和104.9ps偏振模色散引起的差分群时延,比同等条件的最小均方算法提升性能2.23dB。 相似文献
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光子晶体光纤的最内层空气孔在拉制过程中容易发生形变,从而严重影响色散. 基于多极法,模拟了当最内层空气孔为不易发生形变的较小值时,第二、三层空气孔对色散的影响,结果表明这种简单的色散控制方法也可以实现零色散点的快速平移,且保持色散平坦. 以此为基础,设计了应用于C波段具有近零平坦色散的光子晶体光纤,色散系数为-0.24-0.33 ps/(km·nm). 模拟表明,从第五层开始增加空气孔的层数对已设计光纤的色散影响很小,可以通过增加空气孔的层数得到理想的限制损耗. 这一方法亦适用于S,L波段具有类似性质PCF的设计.
关键词:
光子晶体光纤
色散系数
多极法
限制损耗 相似文献
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Optical pulse compression using high-order dispersion compensation is proposed and theoretically analyzed. Firstly, the required
dispersion profile for the high-order dispersion compensation is derived, according to the linear chirp and the nonlinear
chirp of a phase-modulated continuous-wave (CW) laser source. With the use of the high-order dispersion compensation, such
as the combination compensation of the second order dispersion (SOD) and the fourth order dispersion (FOD), an efficient pulse
compression having a less time-bandwidth product and a greater peak power is realized. A sampled fiber Bragg grating (FBG)
with both the SOD and the FOD is then designed using the equivalent chirp and the reconstruction algorithm. Finally, in the
numerical simulation an optical pulse with a time-bandwidth product of 0.79 is generated via high-order dispersion compensation
that is performed by using the sampled FBG. 相似文献
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用于频域光学相干层析成像的深度分辨色散补偿方法 总被引:4,自引:2,他引:2
提出一种深度分辨的色散补偿方法,用于增强频域光学相干层析成像的纵向分辨率。将频域光学相干层析成像采集的干涉谱信号傅里叶变换到空域,获取对应不同深度的干涉谱条纹相位,通过对其进行调整实现对被测样品不同深度处的色散的精确补偿。避免传统方法中采用统一色散系数进行色散补偿所带来的过补偿与欠补偿误差,可以有效消除色散引起的频域光学相干层析成像系统点扩展函数的展宽和扭曲。模拟和实验结果表明,基于深度分辨的色散补偿方法在样品的全深度探测范围内可以达到较佳的补偿效果,可有效提高光学相干层析成像系统的纵向分辨率。 相似文献
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We investigate the dispersion property of space filling mode of photonic crystal structures and find a new type of dispersion—structure induced dispersion. By incorporating this new source of dispersion we designed PCF with large normal dispersion ~ 350 ps2/km. Our simulation indicates the dispersion of such fiber changes less than 3% in 1.4-1.7 μm wavelength range and we also show that our design is insensitive to the structure changes. 相似文献