共查询到20条相似文献,搜索用时 15 毫秒
1.
We present a technique for pulse recovery based on real-time measurement of the differential optical phase spectrum from spectral interference patterns. Using a phase retrieval algorithm we can obtain accurate all order polarization mode dispersion (PMD) information for the optical signal and correspondingly compensate the impairment in optical transmission lines. Linear PMD is accurately extracted from measurements, and analytical simulations show recovery of pulses distorted by higher order PMD. 相似文献
2.
In this paper, by introducing a two-stages polarization mode dispersion (PMD) compensator after a optical fiber link with a large PMD, we compensated over 270ps first-order and 2000ps2 high-order PMD in a optical fiber link with super high PMD. Our experimental results shows that, the compensators based on the two-stages of compensator can be used to PMD compensation in a 20Gb/s OTDM system with 60 km high PMD fiber. Before compensation,270ps DGD is became into max. 7ps after compensation. At simultaneity, the tunable FBG have a function of dispersion compensation. 相似文献
3.
An adaptive polarization mode dispersion (PMD) compensation experiment is reported in a 40-Gb/s phase shaped binary transmission (PSBT) communication system, with the use of a new digital signal processor (DSP)-based optical PMD compensator. PMD tolerance is found to be enhanced by 8 ps after PMD compensation with 1-dB optical signal-to-noise ratio (OSNR) penalty. Under the condition of fast change of states of polarization up to 85 rad/s in the fiber link, the performance of our PMD compensator undergoes the bit error ratio (BER) test for as long as 10 h. 相似文献
4.
Polarization dependent loss (PDL) has been recognized as a critical issue because various inline optical components may have nonnegligible PDL effect that interacts with polarization mode dispersion (PMD).We investigated the impact of PMD-PDL interaction on degree of polarization (DOP), which is the most commonly used feedback signal in PMD compensation. The simulation results of a 40-Gb/s NRZ code optical transmission system show that the maximum PMD increases from approximately 40 ps to more than 45 ps, while minimum DOP declines from approximately 0.6 to approximately 0.2. The interaction of PMD and PDL also induces residual PMD underestimation of 5-8 ps, which causes degradation of PMD compensation performance. 相似文献
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40 Gb/s光时分复用系统中两级偏振模色散自适应补偿实验研究 总被引:1,自引:0,他引:1
偏振模色散效应严重制约着长距离高速光纤通信的发展,偏振模色散的自适应补偿成为光通信领域研究的焦点。利用两阶段偏振模色散补偿器,采用6个自由度的粒子群优化算法(PSO),通过在线监测搜索光纤链路信号的偏振度极值作为反馈控制信息,在40Gb/s归零码高速光纤传输链路中成功实现了ms量级的偏振模色散自适应补偿。补偿前后采用庞加莱球法测量光纤链路中偏振模色散量,测量结果表明在信号中心波长1560.5nm处,差分群时延补偿前后测量值分别为21ps和1.3ps,而二阶偏振模色散补偿前后测量值分别为266ps^2和43.5ps^2。补偿后实验链路中的一阶和二阶的偏振模色散同时得到不同程度的补偿,并且系统的总的功率代价在误码率为10^-9时小于1dB。 相似文献
7.
The variation of polarization mode dispersion (PMD) with V-parameter in single mode optical fibers due to core-ellipticity is studied by performing numerical simulations taking into account both geometrical and thermal-stress-induced birefringences as well as the variation of fiber refractive indices with wavelength. Simple empirical relations are given for calculating the mean PMD for any value of core-ellipticity and V-parameter of a standard single mode fiber. It is observed that the mean PMD saturates for V ? 1.8 leading to very small second order PMD. 相似文献
8.
State of polarization (SOP) and polarization mode dispersion (PMD) are stochastic in nature due to changes in the properties of the optical fibres and its positions because of both intrinsic and extrinsic perturbations. With 184 PMD values obtained by use of the FTB-5700 single-ended dispersion analyzer, the predicted theoretical Gaussian fit was obtained with a mean of 0.47 ps and standard deviation of 0.08 ps. This small standard deviation was justification for its accuracy in measuring PMD of aerial optical fibres. A comparison is also made on the accuracy of the GINTY and the FTB-5700 on measurement of PMD of aerial optical fibres with results showing that the latter is more accurate compared to the former. The time scale over which to compensate PMD in aerial optical fibres was determined and it is slightly higher than 400 s; the decorrelation time obtained for SOPs on a particular windy and hot day. This is because the changes of the PMD vector are known to be slower than SOP changes. 相似文献
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Interchannel cross-phase-modulation-induced polarization scattering (XPMIPS) and its effect on the performance of optical polarization mode dispersion (PMD) compensation in wavelength-division-multiplexed (WDM) systems are studied. The level of XPMIPS in long-haul WDM transmission systems is theoretically quantified, and its effect on optical PMD compensation is evaluated with numerical simulations. We show that in 10-Gbit/s ultra-long-haul dense WDM systems XPMIPS could reduce the PMD compensation efficiency by 50%, whereas for 40-Gbit/s systems the effect of XPMIPS is smaller. 相似文献
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John Cameron 《Fiber and Integrated Optics》1999,18(1):49-59
Polarization mode dispersion (PMD) measurements are presented for a sample of installed optical fibers. High PMD values are fairly common, with 9 of the 71 fibers having PMD coefficients above 0.3 ps km1 2. The results are analyzed in terms of the age of the fibers and the type of cabling. Measurements are presented for a number of concatenated fiber links, and the results show that the PMD value of the link is approximately equal to the square root of the sum of the squares of the PMD values of the individual fibers. 相似文献
13.
CHEN Weicheng XU Wencheng LUO Aiping CUI HuCHEN Yongzhu LIU Songhao 《Chinese Journal of Lasers》2002,11(2):149-153
In this paper, pulse self-trapping robustness to polarization mode dispersion in optical fibers is studied. Nonlinear pulse can be used to suppress PMD despite the input pulse shapes is found. When the nonlinear effect is stronger (initial pulse amplitude is larger), the suppression degree to PMD is better. As the initial chirp is considered, we find that the chirp is harmful to suppress PMD. The more is initial chirp, the more is the PMD value. 相似文献
14.
Heismann F 《Optics letters》2005,30(10):1111-1113
I present numerical simulations of the average transfer function of polarization mode dispersion (PMD) in optical fibers conditioned on various given values of the differential group delay (DGD). I find that even fibers with relatively small mean DGD can exhibit significant coupling between the two principal states of polarization. The average frequency dependence of this coupling can be approximated by a generic analytic function that deviates substantially from the quadratic frequency dependence that is often assumed in second-order PMD models. Finally, I define an extended transfer matrix for first-order PMD that describes the average frequency dependence of all PMD-induced distortions as a function of the DGD and show that this matrix is much better suited for optical PMD compensation than that of a conventional first- and second-order PMD model. 相似文献
15.
In this paper, the first- and second-order polarization mode dispersion (PMD) with the amount of 132.994-ps differential group-delay (DGD) and maximum 476.129-ps/nm second-order PMD can be compensated by a two-stages PMD compensator at a 40-Gb/s optical fiber communication system. The first stage has one free degree that is used for first order and high orders PMD compensations by rotating the state of polarization. The second-stage is used for remainder PMD compensations. After compensation, the average DGD and the maximum second-order PMD are reduced to 345.310 fs and 3.102 ps/nm, respectively. 相似文献
16.
Krzysztof Perlicki 《Optical and Quantum Electronics》2009,41(1):1-10
Low cost statistical PMD/PDL emulator is presented. The emulator was initially designed as a classical PMD emulator. But PDL
measurements of the designed emulator show that it can be also used as statistical PDL emulator. The emulator was constructed
by concatenating 15 highly birefringence optical fiber segments and randomly varying the mode coupling between them, by rotating
the polarization state between them. The achieved numerical and experimental results show that the designed emulator can mimic
the polarization effects (PMD and PDL) of a real modern optical fiber link. 相似文献
17.
In this paper, pulse self-trapping robustness to polarization mode dispersion in optical fibers is studied. Nonlinear pulse can be used to suppress PMD despite the input pulse shapes is found. When the nonlinear effect is stronger (initial pulse amplitude is larger), the suppression degree to PMD is better. As the initial chirp is considered, we find that the chirp is harmful to suppress PMD. The more is initial chirp, the more is the PMD value. 相似文献
18.
Mecozzi A 《Optics letters》2004,29(13):1482-1484
A new method for obtaining the probability density function of polarization mode dispersion (PMD) conditioned on the measured PMD value at an offset optical frequency is introduced. This method is advantageous in its ability to accurately and efficiently estimate the conditional distribution far in the tails. 相似文献
19.
This Letter describes measurements of modal birefringence (MB) and polarization mode dispersion (PMD) of a birefringent single-mode optical fiber for use at 1.5 #x03BC;m in optical wavelength. Optical frequency-domain interferometry based on a fixed analyzer method is applied to the measurement of orthogonal polarization components of light guided in the fiber. An amplified spontaneous emission source having an optical wavelength range between 1520 and 1560 nm is used. A channeled interference spectrum is obtained to measure MB and PMD in turn. These two parameters are not frequency-dependent in the above optical wavelength range and MB = 4.0 #x00D7; 10#x2212;4 and PMD = 1.33 ps/m are obtained. 相似文献