共查询到18条相似文献,搜索用时 109 毫秒
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10 GHz WDM/OTDM通信多波长光脉冲源 总被引:5,自引:4,他引:1
利用色散位移光纤中的复合非线性效应(自相位调制、四波混频、交叉相位调制)得到重复频率10 GHz、谱宽大于50 nm的超连续(SC)光谱,研究了泵浦光功率、波长与生成的SC光谱宽度和平坦度、光脉冲质量的关系.利用AWG从SC谱中滤出4个10 GHz不同波长光脉冲. 相似文献
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NOLM全光波长变换输出脉冲波形特性研究 总被引:2,自引:1,他引:1
本文分析了在利用非线性光学环形镜的开关效应和光纤内交叉相位调制效应实现全光波长变换系统中,色散位移光纤长度、砂浦脉冲峰值功率、泵浦脉冲宽度以及泵浦脉冲和连续探测波之间群速度失配参量对输出脉冲波形特性的影响。通过优化系统各项参数,可以在实现最高转换效率的同时,降低波长变换脉冲扶真程度,使波长变换脉冲无展宽,从而适用于超高速率通信系统。 相似文献
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提出了一种基于色散位移光纤(DSF)的交叉相位调制(XPM)效应的超宽带(UWB)光学生成方法。该方法首先利用DSF的XPM效应实现高功率的高斯泵浦光对低功率的直流探测光的交叉相位调制,然后利用光纤布拉格光栅(FBG)对探测光进行鉴频,实现相位调制到强度调制的转换,从而获得单周期UWB信号。利用光子仿真软件对方案进行了仿真实验,得到了中心频率分别为7GHz和6.95GHz、相对带宽分别为143%和145%的UWB信号,验证了所提方法的可行性。同时,研究了输入信号脉冲宽度、FBG的反射率、鉴频器的类型对产生的单周期UWB脉冲信号波形和频谱的影响。仿真实验的结果表明,该方案对输入信号脉冲宽度不是过宽的情况下具有良好的容忍度,光学高斯带通滤波器、波分复用器和FBG等光滤波器均可作为鉴频器,采用FBG优点是可通过改变反射率灵活地调整产生的UWB脉冲信号的波形。 相似文献
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设计了一种基于色散控制的相位调制锁模掺镱光纤激光器。针对相位调制锁模中模式跳变现象,基于非线性薛定谔方程,建立了光脉冲在光纤激光器系统中演变的数学模型,通过数值仿真研究了色散对脉冲稳定性的影响。在光纤环形腔中加入光子晶体光纤实现色散补偿,解决了输出脉冲在两个相位差为π的模式间跳变引起的不稳定问题。在稳定锁模的前提下,进一步分析了激光器关键参数(非线性系数、小信号增益系数、调制频率和调制深度)对输出脉冲时域特性的影响。结果表明,在腔内平均色散为-19 ps2/km 时,激光器工作在稳定锁模区域,产生重复频率4.918 GHz,脉宽2.54 ps 的锁模脉冲,这对于后续实验中的优化设计具有指导性意义。 相似文献
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采用分布傅立叶方法数值求解耦合的非线性薛定谔方程,模拟了双脉冲在光子晶体光纤中的非线性传输过程,计算和分析了离散效应和脉冲内拉曼散射对信号脉冲传输和压缩的影响。结果表明,当中心波长为800nm的泵浦脉冲在反常色散区进行泵浦,而中心波长为740nm的信号脉冲在正常色散区入射,在群速度色散,自相位调制及交叉相位调制联合作用下,信号脉冲在传输过程中不仅被压缩且存在最佳光纤长度。离散效应不仅导致脉冲压缩比的减小和压缩后峰值功率的降低,而且导致脉冲所需最佳光纤长度的增加以及压缩后的脉冲呈现不对称,还发现,脉冲内拉曼散射有利于改善脉冲压缩质量。 相似文献
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《Optical Switching and Networking》2008,5(4):244-252
An all fiber IM/FSK coding technique for the realization of the 2.5 Gb/s NRZ label swapping onto a 40 Gb/s NRZ payload signal has been numerically studied in this work. Four wave mixing (FWM) and cross phase modulation (XPM) on a dispersion shifted fiber (DSF) are used, for the combination of the Intensity modulated (IM) payload with Frequency Shift Keying (FSK) modulated header synchronously on the same optical carrier, and for the header removal and payload wavelength conversion respectively. Simulations have proven the feasibility of this DSF fiber based method, and shown the potential for high bit rate AOLS applications. 相似文献
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Pendock G.J. Park S.Y. Srivastava A.K. Radic S. Sulhoff J.W. Wolf C.L. Kantor K. Sun Y. 《Photonics Technology Letters, IEEE》1999,11(12):1578-1580
It has been suggested that the level of cross-phase modulation (XPM) produced in erbium-doped fiber amplifiers (EDFA's) may be greater than that produced in the transmission fiber. We measure and compare the levels of XPM produced in an EDFA to that produced in both dispersion-shifted fiber (DSF) and conventional transmission fiber for a 10-Gb/s L-band wavelength-division-multiplexed system. Our results show that, for a system with twenty channels, the levels of XPM produced by our amplifier was negligible compared to that from the DSF, and a factor of approximately nine smaller than for the conventional fiber 相似文献
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Optical phase conjugation (OPC) of multiwavelength signals in a dispersion-shifted fiber (DSF), which can be used for dispersion compensation in the wavelength division multiplexing communication system, is theoretically studied. The multiwavelength phase-conjugate signals are generated by four-wave mixing (FWM) in the dispersion-shifted fiber. There are the pulse-shape distortion and the induced frequency chirping in the phase-conjugate signals owing to pump depletion and the cross-phase modulation among the signals and phase-conjugate signals, respectively. The FWM among the pump wave, signals, and phase-conjugate signals causes unequal conversion efficiencies for the multiwavelength signals and enhances the induced frequency chirping in the phase-conjugate signals. The induced frequency chirping may deteriorate the restoration of the pulse shape. Both the pulse-shape distortion and induced frequency chirping increase with the signal and pump powers. The formula for the induced frequency chirping that is only caused by the signals through cross-phase modulation is derived. The requirement of the signal power in the dispersion-shifted fiber for the restoration of the pulse shape by the optical phase conjugation is estimated and numerically verified 相似文献
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Ting-Kuang Chiang Kagi N. Fong T.K. Marhic M.E. Kazovsky L.G. 《Photonics Technology Letters, IEEE》1994,6(6):733-736
We investigated, theoretically and experimentally, the impact of modulation frequency on cross-phase modulation (XPM) in dispersive fibers. A simple expression for the XPM index has been derived and verified by experiment. The XPM index is found to depend on fiber length, fiber chromatic dispersion, wavelength separation between the signal and the pump, and the intensity modulation frequency. At high modulation frequencies, the XPM index is inversely proportional to the product of the modulation frequency and wavelength separation 相似文献
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Ju Han Lee You Min Chang Young-Geun Han Sang-Hyuck Kim Haeyang Chung Sang Bae Lee 《Photonics Technology Letters, IEEE》2005,17(1):34-36
We experimentally demonstrate a simple and novel scheme for tunable real-repetition-rate multiplication, based on the combined use of fractional Talbot effect in a linearly tunable chirped fiber Bragg grating (FBG) and cross-phase modulation (XPM) effect in a nonlinear optical loop mirror (NOLM). By tuning the group-velocity dispersion of the chirped FBG fabricated with the S-bending method using a uniform FBG, we obtain high quality pulses at pseudorepetition rates of 20/spl sim/50 GHz from an original 8.5-ps 10-GHz soliton pulse train. We subsequently convert this pseudorate multiplication into a real-rate multiplication using XPM effect in an NOLM. A wavelength tuning is also achieved over a /spl sim/15-nm range. 相似文献