共查询到20条相似文献,搜索用时 31 毫秒
1.
三阶色散效应下的二阶光孤子裂变分析与控制 总被引:6,自引:0,他引:6
对光纤中三阶色散效应影响下的二阶孤子传输特性进行了数值模拟,分析了孤子理解变的时域特性及Fourier谱特性,给出了抑制孤子裂变的方法。 相似文献
2.
高阶色散与非线性对高斯脉冲传输特性的影响与讨论 总被引:3,自引:0,他引:3
根据孤子脉冲在光纤中传输所遵从的非线性薛定谔方程,对照相关文献和实验给出的数据,对影响孤子脉冲传输的高阶色散和非线性因素进行了综合分析并得到了一些有意义的结论:在啁啾、三阶色散和五阶非线性同时存在的情况下,它们对脉冲的传输特性都会产生很大的影响,这些因素之间存在着相互影响和制约关系。数值模拟表明,当啁啾、三阶色散和五阶非线性选取某一准临界值时,它们对脉冲存在着增益效应和整形作用。本文所得的结论对光孤子通信的实践过程具有一定的参考意义。 相似文献
3.
应用于接入网段的OFDM射频信号光传输系统宜采用直接调制降低成本和技术复杂度,但射频信号直接调制方式对激光器性能和光纤色散提出更大的挑战。研究了OFDM射频信号直接调制的光传输系统(OFDM直调RoF系统)的传输特性,定量分析了直接调制激光器性能、光纤色散、载波频率及OFDM子载波数等关键参数对OFDM直调RoF系统性能的影响,提出了对OFDM直调RoF系统设计及关键参数设置的建议,研究结果对低成本和低技术复杂度的RoF接入网设计有参考价值和指导意义。 相似文献
4.
利用色散缓变管理孤子消除孤子分裂与变形的方法 总被引:3,自引:0,他引:3
提出了色散缓变管理孤子概念,研究了孤子在该系统中的传输特性。结果表明,色散缓变光纤使孤子脉宽变短效应能有效地抵消孤子脉冲的展宽,只要恰当选择色散强度值,就能获得脉宽、峰值功率和波形都很稳定的孤子传输。 相似文献
5.
高速光通信系统中的色散补偿技术 总被引:8,自引:0,他引:8
高速光纤通信系统中,色散补偿和极化模色散补偿是提高信噪比、改善系统性能的必要手段。本文介绍了几种常用商用传输光纤及其色散特性,分析了相应的色散补偿技术,重点分析了其中普遍采用的色散补偿光纤技术。 相似文献
6.
The dynamic behavior of single-channel transmission on standard fibers with strong dispersion management has been theoretically and numerically analyzed. A single pulse and a pseudorandom pulse sequence have been compared in order to highlight the relevant role played by pulse interaction. A semianalytical theory of the bandwidth evolution demonstrates that the introduction of prechirp is very important for controlling the single pulse propagation and numerical results show that such a chirp also permits to limit the nonlinear pulse interaction when other pulses are present. Simulations of a 40 Gb/s return-to-zero (RZ) system operating in links encompassing step-index fibers, by adopting a periodical compensation of the chromatic dispersion have been performed and results show that a record distance of 1300 km can be achieved with an amplifier spacing of 100 km. A compensation of the fiber third order dispersion would extend the transmission to 1800 km, which corresponds to the limits imposed by the amplified spontaneous emission (ASE) noise of the optical amplifiers 相似文献
7.
Soliton propagation in the presence of polarization mode dispersion (PMD) is studied with an analytical approach. It is shown that there exist two peculiar initial states of polarization that may prevent the soliton to undergo shape distortions. These states coincide with the states that, in the absence of chromatic dispersion and nonlinearity, are usually referred to as principal states of polarization. This fact is used to show that it is possible to improve the performance of an optical transmission system operating in the presence of chromatic dispersion, PMD and Kerr nonlinearity by coupling the input pulses to one of the principal states of polarization 相似文献
8.
A dispersion-compensated optical fiber is proposed for optical soliton propagation. The scheme is studied by a variational approach. Numerical analyses show that the proposed scheme can retain the soliton property for a much longer distance than normal systems. It is shown that, after 48 km, the pulsewidth in the proposed system remains similar to the initial pulsewidth, whereas in the normal system, the pulsewidth has already reached 10 times the initial value. It is demonstrated that significant improvements in soliton propagation characteristics can be achieved by properly cascading fibers with different degrees of group velocity dispersion in finite steps 相似文献
9.
10.
《Lightwave Technology, Journal of》1996,14(3):261-272
In this paper long distances very high capacity NRZ optical transmission systems adopting direct detection are considered in links with a low average chromatic dispersion. Particular attention is devoted to polarization modulated (PM-DD) systems. Polarization modulated systems results to he more degraded with respect to intensity modulated (IM-DD) systems by the light depolarization induced by the interplay among the Kerr effect, the ASE noise of the optical amplifiers and the polarization mode dispersion. The light depolarization is particularly strong in conditions of large spectral broadening that are met when the chromatic dispersion value is maintained very low along the link. On the other hand the use of a fluctuating chromatic dispersion with a mean value equal to zero, whereas the local dispersion is different from zero, shows the double advantage to reduce the chromatic dispersion impairments and to limit the spectral broadening. The advantages offered by this dispersion management technique have been already shown in several experiments for IM-DD systems: in this work we show that this technique is very important also for PM-DD systems since the limitation in the spectral broadening reduces the light depolarization. We show that adopting a suitable dispersion management and an opportune preamplifier optical filter transmissions at 5 Gb/s can be attained in transoceanic links by means of FM-DD systems 相似文献
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12.
Taga H. Yamamoto S. Edagawa N. Yoshida Y. Akiba S. Wakabayashi H. 《Lightwave Technology, Journal of》1994,12(9):1616-1621
We have evaluated the transmission performance of different fiber-chromatic-dispersion-equalization methodologies for ultralong distance IM-DD optical communication systems that use Er-doped fiber amplifier repeaters. The experiment used a 1000 km fiber loop consisting of 30 dispersion-shifted fiber spans and 31 Er-doped fiber amplifiers. We changed the insertion point of the normal single-mode fiber for equalization to change the shape of the accumulated chromatic dispersion. Comparison of the longest transmission distance and the width of the 9000 km transmissible window are discussed for several types of dispersion equalization. The results indicate that the best type of the dispersion equalization for ultralong distance IM-DD optical communication systems is to install dispersion-shifted fibers with short sections of normal single-mode fibers to compensate the accumulated dispersion 相似文献
13.
Zeiler W. Di Pasquale F. Bayvel P. Midwinter J.E. 《Lightwave Technology, Journal of》1996,14(9):1933-1942
A theoretical model is presented for analyzing the propagation of densely spaced WDM optical signals through a cascade of erbium-doped fiber amplifiers and single-mode optical fibers with nonuniform chromatic dispersion. By combining a numerical solution for the EDFA and an analytical expression for FWM components generated through the cascade, the model allows a realistic system analysis which includes gain peaking effect, amplified spontaneous emission accumulation and the effect of dispersion management on the four-wave mixing efficiency. The FWM power distribution at the end of the multi-amplifier transmission link is computed taking into account the phase relation between FWM light amplitudes generated within different sections of the link. The transmission of many WDM channels, evenly spaced around 1547.5 nm, has been analyzed for various dispersion management techniques and propagation distances. Numerical results point out the importance of such a model for a realistic design of WDM optical communication systems and networks. A proper choice of chromatic dispersion, amplifier characteristics, span length, input signal powers and wavelengths, combined with the use of gain equalizing filters, allows to maximize the transmission distance ensuring acceptable signal-to-noise ratio (SNR) and limited SNR variation among channels 相似文献
14.
Taga H. Yamamoto S. Edagawa N. Yoshida Y. Akiba S. Wakabayashi H. 《Lightwave Technology, Journal of》1994,12(6):1042-1046
We have evaluated the effect of fiber chromatic dispersion equalization at the receiving terminal for transoceanic optical communication systems. We used a 1000-km fiber loop with 31 Er-doped fiber amplifiers for the experiments, and measured the bit-error-rate characteristics after 9000-km transmission. Accumulated chromatic dispersion originating from the discrepancy between the signal wavelength and the system zero dispersion wavelength was equalized by the equalization fiber at the receiving terminal. We used both normal and anomalous dispersion fibers at the receiving end. The results have shown that the equalization method of the fiber chromatic dispersion at the receiving terminal is useful with some limitations for ultra-long distance optical communication systems 相似文献
15.
《Lightwave Technology, Journal of》2009,27(10):1369-1378
16.
Iannone E. Locati F.S. Matera F. Romagnoli M. Settembre M. 《Lightwave Technology, Journal of》1993,11(9):1478-1485
The error probability for a single-channel coherent optical differential phase-shift keying (DPSK) transmission system based on repeaterless links in the presence of fiber chromatic dispersion and Kerr effect is evaluated. An accurate model for both the optical signal propagation and the probability distribution of the receiver decision variable is obtained by using a numerical solution of the nonlinear Shrodinger equation and the characteristic function method. The results show that the selection of an optimized IF filter bandwidth is crucial to obtaining the best system performance. When chromatic dispersion dominates, the best performance is achieved in the normal dispersion region whereas when the Kerr effect has the most limiting effect on system performances, the lowest error probability is attained in the anomalous regime. The maximum link length is limited by the presence of Kerr effect, independently of the amount of transmitted optical power, to be shorter than a threshold length if an error probability of 10-9 is to be achieved 相似文献
17.
自傅立叶信号在光纤中的传输特性? 总被引:3,自引:2,他引:1
提出了自傅立叶孤子概念。对自傅立叶孤子信号及自傅立叶高斯信号在光纤中的演变和传输进行了数值模拟和时频分析。结果表明,输入自傅立叶高斯信号,将演变成一类非自傅立叶孤子; 三阶色散效应会影响由自傅立叶高斯信号所演变的孤子的震荡传输幅度,且引起孤子时域延迟、频谱不对称。 相似文献
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19.
Thierry Georges 《电信纪事》1996,51(7-8):313-329
High bit rate long-haul transmission systems on optical fibres are mainly limited by the Kerr effect. Solitons, that balance exactly the Kerr effect by the chromatic dispersion are thus the optimal pulses for fibre transmission. However, the chromatic dispersion associated to the amplifier noise is responsible for a large jitter at receiver end. A calculation of the jitter variance and statistics is presented in this paper. Soliton control techniques can reduce efficiently the jitter variance but they are shown to strongly affect the statistics. It is finally demonstrated that the whole jitter statistics is needed to correctly characterize the soliton transmission system performance. 相似文献
20.
The statistics of PMD-induced chromatic fiber dispersion 总被引:5,自引:0,他引:5
Foschini G.J. Jopson R.M. Nelson L.E. Kogelnik H. 《Lightwave Technology, Journal of》1999,17(9):1560-1565