共查询到20条相似文献,搜索用时 15 毫秒
1.
In this paper, we show that the suppression of intra-channel four-wave mixing (IFWM) in 40 Gbit/s RZ-DQPSK transmission system based on different dispersion maps through using alternate polarization of adjacent symbols. The suppression of IFWM results in significant improvement of system performance. Simulation results show that the amplitude fluctuation is efficiently reduced due to the suppression of the IFWM with alternate-polarization. 相似文献
2.
P. Laurêncio H. Vargues I. Fortes R. Avó M. C. R. Medeiros 《Fiber and Integrated Optics》2013,32(6):441-452
Abstract The performance degradation caused by transmission along dispersive single-mode fibers of optically generated millimeter-wave signals using up-conversion is theoretically assessed and validated by numerical simulation. Up-conversion techniques based on optical double sideband, optical single sideband, and optical carrier suppression are considered. The generation of 60 GHz by frequency tripling using the optical single sideband is shown to be particularly tolerant to the fiber dispersion. The practical imbalance of Mach-Zehnder modulators is taken into account for optical carrier suppression modulation, where the finite extinction ratio is found to increase tolerance to fiber dispersion. 相似文献
3.
Poladian L 《Optics letters》2001,26(1):7-9
The design of wavelength-division-multiplexed (WDM) filters requires control of both the attributes of the filter within the reflection band and the filter's effects on adjacent bands. Causality arguments are used to give the minimum dispersion that can be achieved in the transmission of an adjacent channel in terms of the bandwidth, sidelobe suppression, and channel spacing of WDM filters. The ripple in the side-channel dispersion is also related to the sidelobe properties. Results for a synthesized grating design and its calculated spectrum are compared with the theoretical limits on dispersion. 相似文献
4.
Optical mm-wave generation by using external modulator based on optical carrier suppression 总被引:1,自引:0,他引:1
In this paper, we have theoretically investigated the transmission performance of the optical millimeter (mm)-wave generated by using an external modulator based on optical carrier suppression for the first time. According to our theory, the data signals carried by the optical mm-wave are transmitted in the dispersion fiber without fading but are degraded greatly because of the time shift of the code edges, which still limits the transmission distance. The experimental results agree well with our theory. 相似文献
5.
We develop a tight-binding theory to study the electronic transport through an extended line defect in monolayer graphene. After establishing an analytical expression of the transmission probability, we clarify the following issues concerning the valley polarization in the electronic transport process. Firstly, we find that the valley polarization is robust in the total linear dispersion region. More interestingly, we find that the lattice deformation around the line defect play an important role in tuning the incident angle for complete transmission. Finally, we indicate that next nearest neighbor interaction only causes a small suppression to the valley polarization. 相似文献
6.
鉴于相干光正交频分复用系统(CO-OFDM)易受非线性效应影响,严重制约系统传输性能, 提出一种基于星座恢复的降低系统峰均值功率比(PAPR)的方法。对系统模型及作用机理进行分析,仿真结果显示,以10 Gbit/s的速率通过单模光纤传输720 km,基于星座恢复的CO-OFDM系统Q值较无非线性抑制的CO-OFDM系统有3 dB提高;另外,系统最佳限幅比例系数受色度色散影响,随着色散因子的增大,星座恢复效果也逐渐减弱,在传输240 km条件下,色散因子为12 ps/nmkm较6 ps/nmkm,限幅比例系数从0.9降低至0.8。 相似文献
7.
George E. Ponchak Linda P. B. Katehi 《International Journal of Infrared and Millimeter Waves》1997,18(2):369-382
Design rules for Layered Ridge Dielectric Waveguide (LRDW) are presented for the first time through simple figures and closed
form equations. The Effective Dielectric Constant (EDC) method is used to develop the design rules that account for typical
circuit specifications such as higher order mode suppression, dispersion, attenuation, and coupling between adjacent transmission
lines. Comparisons between the design of LRDW, image guide, and millimeter-wave dielectric ridge guide are made. 相似文献
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设计并研制了带电色散补偿功能的10 Gb/s脉冲转换器。电色散补偿通过时域均衡的方法,消除光纤色散带来的码间串扰;将电色散补偿芯片纳入脉冲转换器设计中,从而提高了其传输距离。所研制的样品光发射部分采用分布反馈激光器加电吸收调制器集成光源,接收部分采用带互阻放大器的雪崩光电二极管光电探测器模块,电色散补偿芯片对光电探测器输出的码流执行色散补偿算法。对样品进行的测试结果表明该脉冲转换器背对背接收灵敏度为-24.6 dBm,经过100 km G.652光纤传输后接收灵敏度为-20.8 dBm。未加电色散补偿功能时,采用相同的光源传输距离仅为50 km。 相似文献
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利用相位共轭与色散配置实现具有大占空比和大放大器间隔的长距离光孤子传输 总被引:2,自引:1,他引:1
在用光纤放大器补偿损耗的光纤传输线中,用负色散光纤与正色散光纤或色散补偿器件交叉配置,并使传输线中光纤的有效色散适当大于(与平均孤子对应的)理论值,同时在传输线中周期地使用相位共轭器,可以在把放大器间隔提高到与常规光纤通信相同的条件下有效地削弱孤子之间的互作用。本文对实现速率为25Gbit/s、占空比为1/2、光放大器间隔为100km、传输距离大于6000km的光孤子传输作出了数值论证 相似文献
13.
In this paper, we carry out, by numerical simulations and experiments on recirculating loop, a comparative analysis of the performances of two types of dispersion management techniques for 160 Gb/s transmission systems, which correspond to short-period dispersion maps (dense dispersion management) and long-period dispersion maps (conventional dispersion management), respectively. We show that the dense dispersion management system suffers performance degradation by the effects of polarization mode dispersion (PMD) and fiber splicing losses, in a more dramatic manner than in the system with long-period map. We experimentally find that, at constant PMD, dense dispersion managed system permits to achieve a transmission distance that is twice larger than that obtained with the conventional dispersion management; however, the polarization mode dispersion significantly reduces the gap between the transmission performances of the two types of systems. 相似文献
14.
Malomed BA 《Optics letters》1998,23(16):1250-1252
Enhancement of jitter suppression of a soliton by combination of fixed-frequency filters with periodic dispersion compensation is predicted in an analytical form by means of the Fokker-Planck equation for the soliton's random walk. The result depends on the dispersion-compensation period but not on the ratio of the dispersions. Another result is presented that can help one to understand jitter suppression by dispersion compensation without filters, which was observed in recent experiments. 相似文献
15.
S. V. Danilova E. S. Ivanova A. K. Malyshkin G. I. Ovchinnikova Yu. A. Pirogov 《Physics of Wave Phenomena》2013,21(3):231-234
Microwave dielectric spectra of ferroelectric triglycine sulfate are measured in the littlestudied frequency range from 90 to 150GHz, and the suppression of low-frequency dielectric anomaly by microwaves at these frequencies is investigated. It is shown that suppression occurs only in the range of non-Debye dielectric dispersion. An additional dispersion mechanism based on the activation-diffusion model of orientational polarization and transit-time effects for quasi-free carriers is proposed to explain the microwave impact. 相似文献
16.
It is proposed that the high dispersion at the transmission band edges of uniform long period gratings (LPG) fabricated on relatively high Δ fibers can be used for efficient dispersion compensation. Since the transmission of LPG varies with length of the grating or refractive index modulation, we show that it is possible to tailor the transmission spectrum to obtain high transmission with constant dispersion and negligible delay ripple over a reasonable bandwidth. Since the proposed structure works in transmission it should be suitable for fiber optic communication links. 相似文献
17.
Broadening of the pulse waveforms by the higher-order dispersion of a transmission line is a critical limiting factor in achieving terabit-per-second optical time-division multiplexed (OTDM) transmission with femtosecond pulses. We show that the third- and fourth-order dispersion of a transmission line can be simultaneously compensated for by use of a phase modulator. In this method, sinusoidal phase modulation applied to the linearly chirped pulse before transmission compensates for the phase shift caused by the third- and fourth-order dispersion of the transmission line. The pulse broadening of a 380-fs pulse after a 70-km transmission in a 1.28-Tbit/s OTDM experiment was as small as 20 fs. 相似文献
18.
Nearly zero ultraflattened dispersion in photonic crystal fibers 总被引:24,自引:0,他引:24
We present a procedure for achieving photonic crystal fibers with nearly zero ultraflattened group-velocity dispersion. Systematic knowledge of the special guiding properties of these fibers permits the achievement of qualitatively novel dispersion curves. Unlike the behavior of conventional fibers, this new type of dispersion behavior permits remarkably improved suppression of third-order dispersion, particularly in the low-dispersion domain. 相似文献
19.
R. S. Kaler T. S. Kamal Ajay K. Sharma Sandeep K. Arya R. A. Agarwala 《Fiber and Integrated Optics》2002,21(3):193-203
By using large signal analysis for dispersive optical fiber, the FM-AM conversion with respect to binary intensity modulated PCM systems including second order dispersion term is discussed. The modified expression for power penalty has been derived and its impact on laser linewidth and bit rate has been investigated. For power penalty less than 0.5 dB, the plots between bit rate and transmission distance are plotted. It is seen that the transmission distance increases with decrease in linewidth over significant bit rates. The transmission distance with first order dispersion term for 300 MHz linewidth is approximately 800km. With proper first order dispersion compensation, i.e., with second order dispersion only, the transmission distance can be enhanced to 10 8 km for this linewidth. The linewidth requirements for systems with different bit rates and transmission distances are also calculated and discussed. Further, it is seen that by including the second-order dispersion term, the bit rate and transmission distance decreases. For higher linewidths, this decrease in bit rate and transmission distance is very less and vice versa. For 300 MHz linewidth, the decrease in transmission distance is just 30 km, and for 30 MHz linewidth, the decrease is approximately 600 km over significant bit rates. 相似文献
20.
量子信息在光纤中传输时,会受到光纤损耗、色散、非线性效应等多因素的影响,将产生传输态的演化与能量转移.本文以单模光纤传输方程以及电磁场量子化理论为基础,对单模光纤中基模模场进行量子化处理,推导并建立了考虑损耗、色散、非线性效应后的单光子传输方程.基于微扰法对单光子非线性传输方程进行了求解,给出了稳定解存在的必要条件及其所满足的色散方程.深入讨论了广域光功率随微扰频率的变化关系,并且分析了光纤色散、非线性效应对解的影响.为量子光纤传输系统性能的深入研究奠定了理论基础. 相似文献