共查询到18条相似文献,搜索用时 109 毫秒
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利用均匀相位掩模板制作线性啁啾光纤光栅 总被引:3,自引:1,他引:2
理论上分析并从实验上验证了一种利用均匀相位掩模板写入啁啾光纤光栅的方法:将光纤弯曲,由于光纤离掩模板的距离不同从而使光纤光栅的周期轴向渐变,由此产生啁啾。分析了这种啁啾光纤光栅的谱特性和时延特性,同时也分析了由于光纤离掩模板的距离不同而引起的折射率调制变化给光纤光栅特性带来的影响。设计了一种石英曲面,利用其使光纤按照弯曲函数进行弯曲,然后进行紫外曝光制成了线性的啁啾光纤光栅。实验中制作的啁啾光纤光栅色散值为-1102 ps/nm,纹波为17ps。通过改变弯曲函数就可以实现利用一块均匀相位掩模板制作不同啁啾量的啁啾光纤光栅的目的,降低了啁啾光纤光栅的制作成本。 相似文献
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非对称切趾对啁啾光纤光栅特性优化的分析 总被引:2,自引:0,他引:2
基于对啁啾光纤布拉格光栅反射谱和时延曲线的分析,引入非对称切趾技术。综合时延曲线纹波和反射谱纹波平滑两方面考虑,将对称切趾技术的最佳切趾比例、左移和右移两种非对称切趾技术以及采用不同切趾函数对光纤光栅特性参量的优化效果进行了分析和比较。结果表明,与对称切趾相比,左移非对称切趾可避免对称切趾中为增大反射谱带宽而减小切趾比例使时延纹波增大的缺点,在保持反射谱纹波基本不变的前提下将时延曲线纹波降低了43.5%(与实验结果39.9%相吻合)。此外,与仅用汉明函数切趾相比,光纤光栅左端采用超高斯函数、右端采用汉明函数的非对称切趾方式使反射谱平坦部分纹波减小了89.3%,对应的时延曲线拟合误差减小了16.7%,获得了更好的优化效果。 相似文献
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分析了光纤光栅不理想特性的产生机理,对以啁啾光纤光栅为色散补偿器的10Gb/s光传输系统中,啁啾光纤光栅的不理想特性包括群时延纹波、反射纹波及光栅通带带宽对采用归零码(RZ)、非归零码(NRZ)以及载波抑制归零码(CSRZ)三种调制格式传输系统性能的影响进行了详细的数值分析和比较. 同时进行了基于光纤光栅色散补偿的1500km无误码传输实验,通过对啁啾光纤光栅由于不理想特性的差别而导致对实际传输系统不同信道性能影响的比较,进一步验证了仿真分析的正确性.
关键词:
光传输
啁啾光纤光栅
不理想特性
调制码型 相似文献
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40Gb/s光时分复用传输光纤光栅补偿色散研究 总被引:8,自引:1,他引:7
用精密扫描掩模法写入宽阻带啁啾光纤光栅,掩模板背面两端各10%长度处镀有按4阶高斯函数透过率的膜,写入的啁啾光栅的时延纹波最大值为20ps。为减少写入光纤光栅的偏振模色散,研制了新的低偏振模色散光纤光栅补偿写入法。采用补偿写入法前的平均微分群时延为9.1406 ps;采用补偿写入法后的平均微分群时延为0.1521 ps。并利用低偏振模色散光纤光栅对40Gb/s光时分复用系统在普通G.652光纤传输122km的色散进行了补偿实验,功率代价为1.5dB。 相似文献
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用布拦格光纤光栅制作啁啾光纤光栅 总被引:1,自引:1,他引:0
介绍了一种用布拉格光纤光栅制作啁啾光纤光栅的方法。采用氢酸腐蚀布拉格光纤光栅,使光栅的横截面沿光栅轴向逐渐变小,然后对光栅施加1.50N的拉力,在光栅轴向建立应变梯度,制作出长15mm、峰值反射率达92%、反射半高宽为5nm的啁啾光纤光栅。 相似文献
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对利用零级抑制均匀相位掩模版结合同透镜制作啁啾光纤光栅的技术进行了详细的理论和实验研究。结果表明这种方法适合于制作啁啾参数较小的光纤光栅,当所制作的光栅啁啾参数较大时,将导致严重的光谱不对称性和包层模耦合。 相似文献
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通过对光栅制作过程的优化设计,解决了光纤光栅温度稳定性、纹波系数、带宽、偏振模色 散补偿等关键技术,所制作光纤光栅已经达到温度系数小于00005 nm/℃,带宽大于14 nm,纹波系数小于50 ps,色散量超过 -1000 ps/nm的先进水平. 采用琼斯矩阵本征值法较 精确地测量了光栅的偏振模色散,并对其进行了补偿,光纤光栅色散补偿器的偏振模色散由 补偿前的91406 ps改善为补偿后的01521 ps. 在此基础上,成功地建立了一个稳定可靠 、速率为40 Gb/s,传输链路为122 km G
关键词:
高速光通信系统
普通单模光纤
光纤光栅
色散补偿 相似文献
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We investigated the performance limitation of a frequency-tunable photonic microwave notch filter incorporating a chirped fiber Bragg grating (FBG) as a group delay line. In particular, we carried out theoretical and experimental studies to analyze the impact of the reflectivity ripple (RR) and group delay ripple (GDR) in the chirped FBG on the output notch performance. The results of experimental and theoretical analyses performed on a photonic microwave notch filter in which an S-bending-based linearly chirped FBG was incorporated, revealed that the notch depth and notch frequency were significantly affected by imperfections in the chirped FBG. The notch depth was found to be decreased by the RRs, whereas significant fluctuations in the notch frequency were caused by the GDRs. On the basis of the obtained results, we conclude that the RR and the GDR are the fundamental factors that degrade the performance of chirped FBG-based photonic microwave filters. 相似文献
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光纤光栅非线性时延对啁啾的电视信号的影响 总被引:1,自引:1,他引:0
分析了有线电视系统中,用作色散补偿的光纤光栅因色散抖动对信号载波互调比产生的影响,结果显示色散抖动对有线电视信号互调比的影响随拦动幅度、抖动周期、信道数目的加而增加,信道频率的分布也对其的影响。对光栅的色散特性进行数值估算,发现常耦合系数线性啁啾光栅不能用的有线电视系统中进行色散补偿。 相似文献
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Apodization is a crucial technology for improving the dispersion performance of fiber Bragg gratings (FBGs). In this paper, we focus on how to select an optimal apodization for chirped fiber Bragg gratings and demonstrate a novel apodization selection method capable of choosing the optimal apodization based on the relationship between the bandwidth change and variation in average group delay ripple (GDR). Compared with current approaches, the novel method can select an optimal apodization profile and parameter for FBGs easily and accurately. Two numerical experiments are used to demonstrate the advantages of this method, one exhibits the different performances of five different apodization profiles, the other evaluates the influence of FBG parameters such as grating length, period, chirp, and index change on the apodization performance. 相似文献
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Stable Dual-Wavelength Fibre Laser with Bragg Gratings Fabricated in a Polarization-Maintaining Erbium-Doped Fibre 总被引:1,自引:0,他引:1 下载免费PDF全文
A new polarization-independent duai-wavelength fibre laser by fabricating a uniform FBG and a chirped FBG in a polarization-maintaining erbium-doped fibre (PM-EDF) is proposed and demonstrated. The wavelength spacing is 0.18nm and the optical signal-to-noise ratio is greater than 50dB with pump power of 246mW. Chirped FBG is used to make the reflectivity wavelengths of two PM-FBGs match easier. Since both EDF and FBGs are polarization-maintaining without splices and the two wavelengths are polarization-independent, the maximum amplitude variation and wavelength shifts for both lasing wavelength with 3-min intervals over a period of six hours are less than 0.2 dB and 0.005 nm, respectively, which shows stable dual-wavelength output. 相似文献
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This paper presents an overview of fiber Bragg gratings (FBGs) fabrication principles and applications with emphasis on the
chirped FBG used for dispersion compensation in high-speed optical communication systems. We discuss the range of FBG parameters
enabled by current fabrication methods, as well as the relation between the accuracy of FBG parameters and the performance
of FBG-based dispersion compensators. We describe the theory of the group delay ripple (GDR) generated by apodized chirped
fiber gratings using the analogy between noisy gratings and superstructure Bragg gratings. This analysis predicts the fundamental
cutoff of the high frequency spatial noise of grating parameters in excellent agreement with the experimental data. We review
the iterative GDR correction technique, which further improves the FBG quality and potentially enables consistent fabrication
of FBG-based dispersion compensators and tunable dispersion compensators with unprecedented performance. 相似文献
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The system of L-band 2×10 Gb/s WDM transmission over conventional single mode fibre with 600 km by chirped fibre Bragg gratings dispersion compensation 下载免费PDF全文
A chirped fibre Bragg grating according to ITU-T suggested L-band
(2nd channel $\lambda _{1}=1570.83$~nm; 80th channel $\lambda
_{2}=1603.57$ nm) with more than 1800 ps/nm single channel dispersion
compensation is presented in this paper, of which the cladding mode
loss, the delay curve ripple and the power fluctuation of the
reflected spectrum are less than 0.5 dB, 50 ps and 0.25 dB,
respectively. With this new FBG as dispersion compensation device, a
$2\times 10$ Gb/s wavelength division multiplexing (WDM) L-band
transmission of 600 km based on conventional single mode fibre (G.652
fibre) is performed without forward error correction. The bit error
rate (BER) is less than 10$^{ - 12}$ and the power penalties of the
2{nd} and 80{th} channel of L-band are 1.8~dB and 2.0~dB,
respectively. 相似文献
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利用遗传算法优化线性啁啾光栅性能 总被引:3,自引:2,他引:1
针对制作町用于40 Gb/s全光色散补偿的宽带线性啁啾光栅时出现带内群时延纹波波动较大等问题.提出了一种通过设计和改变切趾函数的参量来优化线性啁啾光栅的新方法.该方法实现简单.只需根据需要设计具有不同滚降特性的切趾函数,同时利用遗传箅法来优化切趾参量.结合传输矩阵法经过200代获得了低带内时延纹波的线性啁啾光栅.数值结果验证了采取非对称分段切趾法在保持反射谱宽和平坦性的同时可以抑制带内群时延纹波的优越性.利用该方法制作了反射谱工作带宽为1.06 nm、时延纹波不超过45.60 ps、可用于大容量密集波分复用系统(DWDM)色散补偿的线性啁啾光纤光栅. 相似文献