共查询到19条相似文献,搜索用时 203 毫秒
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交叉相位调制产生调制不稳定性的基态增益谱 总被引:5,自引:1,他引:4
在考虑光纤损耗的情况下,从非线性薛定谔方程出发,推出了交叉相位调制(XPM)所致财制不稳定性(M)的基态增益谱。研究结果表明,XPM产生的MI不仅在光纤反常色散区可以产生,而且在正常色散区也可以产生;光纤损耗不仅影响增益谱的下降,而且影响增益范围减小。 相似文献
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在三五阶非线性共存时,研究了有损耗单模光纤中基于两光波交叉相位调制的不稳定条件和增益谱.在色散缓变光纤正色散区,分析了五阶非线性系数、色散纵向变化参量以及两扰动的频率大小关系对交叉相位调制不稳定增益谱的影响.结果表明,在五阶非线性下,色散的纵向渐减仍有利于展宽调制不稳定增益谱;正五阶非线性可使增益谱的谱宽和谱峰值增大,并使谱峰位置远离主波频率,负五阶非线性的作用则相反;两扰动频率大小关系不同,色散纵向参量的变化对增益谱的谱峰大小和位置的影响也不同,五阶非线性对交叉相位调制不稳定性的加强或抑制程度也不同. 相似文献
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五阶非线性色散缓变光纤负色散区的交叉相位调制非稳 总被引:2,自引:2,他引:0
推导了三、五阶非线性共存时有损耗单模色散缓变光纤中同偏振、不同波长的两光波的交叉相位调制不稳定条件和增益谱。在色散缓变光纤负色散区,详细分析了五阶非线性系数、色散纵向变化参量、两扰动的频率大小关系对交叉相位调制不稳定条件和增益谱的综合影响。结果表明,正、负五阶非线性分别对交叉相位调制不稳定性起加强和抑制的作用;两扰动频率大小关系不同,色散纵向参量的变化对调制不稳定增益谱的影响也不同;随参数的不同,增益谱存在有截止频率和无截止频率2种形状。 相似文献
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高阶色散下与扰动频率相关的调制不稳定性 总被引:1,自引:0,他引:1
对包含损耗、二至四阶色散下两光波扰动频率相等与不等的情况,分析了光纤不同色散区的交叉相位调制不稳定性条件和增益谱.结果表明:三阶色散对交叉相位调制不稳定条件和增益谱无影响,但对扰动的有效波数有贡献;四阶色散的存在,使得二、四阶色散皆同号时的不稳定性比只有二阶色散的情形多出了远离零点的额外谱区,随两扰动的频率大小关系不同,该额外谱区可能由紧挨的2个小谱区构成,也可能只是单一的谱区;增益谱两大区域的谱宽和峰值也会随两扰动频率的不同而发生变化;四阶色散的存在还使两光波的二阶色散异号时的不稳定性出现了远离零点的增益谱. 相似文献
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零色散附近的调制不稳定性 总被引:3,自引:0,他引:3
在同时考虑光纤损耗及高阶色散的前提下,从广义的非线性Schroedinger方程出发,研究了单模光纤在零色散附近的调制不稳定性。研究表明,当光脉冲工作在最小群速度色散附近时,四阶色散对光纤的调制不稳定性起决定作用,它使最大微扰频率向临界微扰频率靠近;研究同时发现,光纤损耗亦对增益谱的谱宽有较大影响,它使增益的谱宽变窄,且影响程序随着入峰值功率及传输距离的增大而增强。 相似文献
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基于双折射光纤中光脉冲传输方程,详细分析了二阶色散、自相位调制以及交叉相位调制在光脉冲传输过程中引起的啁啾。分析结果显示:通过合理选取入射功率,二阶色散引起的啁啾与自相位调制引起的啁啾在脉冲中心附近可以相互抵消,从而使脉冲展宽最小;交叉相位调制产生的两偏振分量的啁啾引起的频移,可使两偏振分量间产生互束缚,利用这种现象可以抑制偏振模色散。 相似文献
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利用数值计算的方法对40G WDM系统进行了仿真.在考虑了光纤群速度色散(GVD)、三阶色散(TOD)、自相位调制(SPM)、交叉相位调制(XPM)、四波混频(FWM)和偏振模色散(PMD)的前提下,通过对比眼图和Q因子,对归零码(RZ)和非归零码(NRZ)调制格式的传输性能进行了研究. 相似文献
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多周期色散管理系统中交叉相位调制产生的相移研究 总被引:1,自引:1,他引:0
以泵浦探测波结构为例,针对多周期色散管理系统,研究了色散作用下交叉相位调制产生的相位移动,推导了多段放大线路中色散作用下交叉相位调制产生的相移表达式,对该表达式进行简化得到了特定线路中色散作用下交叉相位调制所致的相移表达式。研究表明,线路总相移正比于传输线路中的光纤段数,随着调制频率的提高,相移量总体趋势逐渐减小,局部出现极大极小波动,且波动周期随走离参量增大逐渐减小,在高频段色散对交叉相位调制产生的相移产生显著影响,随着调制频率的提高,色散对相移的贡献正负交替变化,解析和仿真结论能较好吻合。 相似文献
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Marks B.S. Menyuk C.R. Campillo A.L. Bucholtz F. 《Lightwave Technology, Journal of》2006,24(6):2305-2310
A technique for computing the effect of cross-phase modulation (XPM) on two copropagating analog channels in an optical fiber link is presented. In this approach, the interaction between the two channels is linearized by keeping the self-phase modulation (SPM) and XPM interactions in the strong optical carrier components only at lowest order and then at the next order, deriving the effect on the modulation components of both channels when the optical carrier is strong relative to the other components of the channel. In contrast to some previously suggested approaches, it is not assumed that the pump is undistorted, and therefore, this method accurately describes distortions due to SPM, XPM, and dispersion management in both channels. This method is easily applied to systems with multiple spans employing dispersion management with loss and gain. The expressions for the received radio frequency power and crosstalk between the two channels when direct detection is used are then provided. Using this approach, new expressions for the amplitude modulation and phase modulation modes of the two channels are derived, and the way they exchange energy when SPM, XPM, and dispersion are all considered is explained. This method yields excellent agreement between theory and experimental data. 相似文献
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A coupled-mode formulation in the frequency domain has been developed and applied to the analysis of the modulation instability (MI) due to the self- and cross-phase modulations (SPM and XPM) in optical fibers. The modulation instability of two copropagating beams with the same polarization at different carrier frequencies is examined in detail. It is demonstrated that, by identifying the phase-matching conditions among different sideband components, the modulation instability due to the SPM and the XPM may be described by a set of reduced coupled-mode equations. Simple analytical expressions for the gain are derived under this condition. The approximate formulas are compared with the full wave solutions and their scopes of validity are discussed 相似文献
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Shilong Pan Caiyun Lou 《Quantum Electronics, IEEE Journal of》2008,44(3):245-253
A numerical model for multiwavelength actively mode-locked erbium-doped fiber lasers (AML-EDFL) is presented. Using the model, the influences of four-wave mixing (FWM) and phase modulation effects (i.e., self-phase modulation (SPM) and cross-phase modulation (XPM)) can be studied, respectively. We use it to investigate AML-EDFLs incorporating a highly nonlinear fiber (HNLF) and explore the mechanisms for gain competition suppression (GCS). The net dispersion of the cavity is found critical for GCS. In the small dispersion regime, FWM dominates GCS, but SPM and XPM deteriorate the output pulses. In the large anomalous dispersion regime, SPM and XPM, however, enhance GCS and produce high-quality pulses. Degree of GCS is also quantitatively evaluated. The simulation results are at last confirmed by experiments. 相似文献
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本文数值模拟了强度调制光信号在级联光纤放大器常规SMF通信系统中的传输,在模拟中主要考虑了自相位调制、群带色散和ASE噪声。我们使用负色散补偿光纤去补偿群速色散和自相位调制。结果表明如果色散得到很好的补偿,当放大器的间距减少到50kM时,无误码2050km传输是可能的。 相似文献