共查询到20条相似文献,搜索用时 0 毫秒
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光纤无线通信系统中用高非线性光纤实现全光频率上转换 总被引:2,自引:0,他引:2
研究了一种基于高非线件光纤(HNLF)中交叉相位调制效应的全光频率上转换射频耦合到光纤无线通信(ROF)系统.数值计算结果表明,由于交叉相化调制引起的调制不稳定性.波长1.54μm,重复频率为40 GHz的抽运光可使波长为1.56μm,载有速率为2.5 Gbit/s的非归零码作为下行链路数据的弱信号光光波分裂,产生与载波距离为40 GHz且与载波相干的两个一阶调制边带,抽运光脉宽、抽运光功率和光纤长度对载波与边带功率差有较大影响.仿真实验结果证实了以上原理,速率为2.5 Gbit/s的数据信号在高非线性光纤中被上转换到40 GHz毫米波上.信号光功牢为0 dBm时,得到的优化光纤长度为600 m,抽运光功率为17 dBm. 相似文献
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Analytical Solution for SOA-Based All-Optical Wavelength Conversion Using Transient Cross-Phase Modulation 总被引:1,自引:0,他引:1
Dong J. Fu S. Zhang X. Shum P. Zhang L. Huang D. 《Photonics Technology Letters, IEEE》2006,18(24):2554-2556
All-optical wavelength conversion (WC) based on transient cross-phase modulation (T-XPM) of semiconductor optical amplifier (SOAs) is a promising approach to accelerate the gain recovery of SOAs. An analytical solution is deduced to explain the polarity variation of WC based on T-XPM of SOAs from the viewpoint of the impulse response functions. We conclude that both inverted and noninverted WCs can be realized when the central wavelength of the optical bandpass filter is either blue-shifted or red-shifted with respect to the wavelength of the probe signal. We are able to validate the formula against our experimental results recently published 相似文献
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《Photonics Technology Letters, IEEE》2008,20(23):1893-1895
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Polarization-independent all-optical retiming is demonstrated experimentally at 10 Gb/s using a self-pulsating distributed feedback laser, cross-phase modulation in a highly nonlinear fiber, and spectral slicing. With careful attention to key design parameters, excellent performance is achieved without additional complexity compared to a conventional polarization-dependent implementation. 相似文献
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Jian Zhao Zhaohui Li Dawei Liu Linghao Cheng Chao Lu Tam H.Y. 《Lightwave Technology, Journal of》2009,27(23):5295-5301
In this paper, we demonstrated a signed chromatic dispersion (CD) monitoring method of 10 GHz nonreturn-to-zero differential phase-shift keying (NRZ-DPSK) and return-to-zero differential phase-shift keying (RZ-DPSK) signals by using asynchronous delay-tap sampling and an imperfect tuned delay interferometer. This method could monitor not only the value but also the polarity of residual CD. The demodulated signals show amplitude shoulders on the rising edge or the trailing edge with CD accumulation. Delay-tap sampling scatter plots could reflect this signal distortion by a unique characteristic and realize the signed CD monitoring. The monitoring range can be up to plusmn400 and plusmn720 ps/nm for NRZ-DPSK and RZ-DPSK signals, respectively. Simulation and experimental results are also proposed. 相似文献
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《Quantum Electronics, IEEE Journal of》2009,45(1):51-58
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We propose and experimentally demonstrate an all-optical phase multiplexing scheme using four-wave mixing in a highly nonlinear fiber. Two 10-Gb/s pi/2-shifted return-to-zero (RZ) differential phase-shift-keying (DPSK) wavelength-division-multiplexing (WDM) signals are successfully phase-multiplexed into a 20-Gb/s RZ differential quadrature phase-shift-keying signal with a negative 1.6-dB power penalty. With more input DPSK WDM signals, the proposed scheme can be applied to obtain a multilevel phase-shift-keying signal with increased capacity and enhanced spectral efficiency. 相似文献
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在同时考虑到光纤的二至四阶色散和三、五阶非线性的情况下,研究了四阶色散、五阶非线性以及入纤功率对双光束交叉相位调制(XPM)不稳定性的综合影响。研究表明,在高阶色散下,正负五阶非线性的存在仍然分别对交叉相位调制不稳定性起加强和削弱的作用;三阶色散对不稳定性增益谱无影响;当四阶和二阶色散系数同号时,四阶色散的存在导致交叉相位调制不稳定性增益谱出现一个新的远离零点的第二谱区,且该谱区由两个始终相连的小谱区组成;第一谱区的谱峰与第二谱区中靠近零点的小谱区的谱峰相当;随着其中一束光的入射功率的增加,两大谱区从分离到靠近再到合二为一,从三个谱峰过渡到两个谱峰;正(负)色散区的第二谱区中靠近(远离)零点的小谱区的谱峰和谱宽很小。在其他色散区时,不稳定性增益谱则只有第一或第二谱区。 相似文献
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高阶色散和饱和非线性下的交叉相位调制不稳定性 总被引:1,自引:1,他引:1
从光纤中包含饱和非线性和高阶色散的耦合非线性薛定谔方程组出发,采用线性稳定性分析法,研究了高阶色散和饱和非线性对双光束交叉相位调制不稳定性的综合影响.研究表明,当四阶和二阶色散系数同号时,调制不稳定性增益谱可能出现一个新的远离零点的第二谱区,且该谱区由两个始终相连的小谱区组成;第一谱区的谱峰与第二谱区中靠近零点的小谱区的谱峰相当;在其他色散区,增益谱只存在一个谱区.而饱和非线性的存在则使每个谱区的谱宽、峰值增益大小随入纤功率的增大呈现出先增大后减小的特点,即对每个谱区而言,将出现两个不同的输入功率对应同一个不稳定增益峰值和谱宽的情形. 相似文献
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简单地推导了相位调制下的单音频率在传输光纤中其功率与光纤色散、光纤距离之间的关系,并介绍了在DWDM系统中可以利用相位调制法进行实时监测色散。此方法对于40GHz系统的色散实时监测提供了很好的参考方法。仿真结果表明,在未考虑光纤非线性效应的情况下有很高的精确性,当考虑非线性效应时,其传输距离会由于传输速率的影响而受到限制。 相似文献
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饱和非线性光纤正色散区的交叉相位调制不稳定性 总被引:1,自引:0,他引:1
在考虑到光纤饱和非线性效应的情况下,给出了同偏振、不同波长的两光波的慢变振幅满足的耦合非线性薛定谔方程组以及线性化后微扰满足的方程组。在光纤的正色散区,分析并讨论了交叉相位调制不稳定增益谱随两光波输入功率变化的规律。结果表明,与饱和非线性光纤中自相位调制不稳定性的增益谱类似,交叉相位调制不稳定增益谱的临界扰动频率、峰值增益大小随两光波输入功率的增大也呈现出先增大后减小的特点,而二者随两光波输入功率变化的快慢都与两扰动的频率大小有关,即会出现两个不同的输入功率对应同一个不稳定增益峰值和临界扰动频率的情形。 相似文献
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As shown by Chianget al.(1996), cross-phase modulation on each channel of a wavelength-division-multiplexed transmission system can be viewed as a phase modulation, where the modulating signal is the sum of the input intensities of all the other copropagating channels, each filtered by a low-pass filter, whose bandwidth decreases with the walk-off parameter. We give an explicit expression of the impulse response of such filter in the general case of dispersion mapped transmission systems. We show by simulation that this filter, in intensity-modulated transmission systems, gives an optimal prediction of the signal phase even when the underlying assumption of negligible envelope distortion upon which its derivation is based is strongly violated. As an application, we show an analytical evaluation of the spectral broadening induced by XPM in multi-span compensated systems. 相似文献
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《Quantum Electronics, IEEE Journal of》2009,45(3):223-232
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文章提出一种新型的光载波抑制一差分相移键控(OCS-DPSK)调制格式,可以实现光载无线(RoF)系统的3个关键功能:分发下行RoF信号、产生远端本振信号和上行数据的重调制,从而实现成本最优的RoF接入网络。文章作者实验演示了基于单个单臂马赫-曾德调制器产生OCS-DPSK控调制格式的全双工RoF传输系统。 相似文献
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Self-Pumping Wavelength Conversion for DPSK Signals and DQPSK Generation Through Four-Wave Mixing in Highly Nonlinear Optical Fiber 总被引:1,自引:0,他引:1
Zhou G. T. Xu K. Wu J. Yan C. Su Y. Lin J. T. 《Photonics Technology Letters, IEEE》2006,18(22):2389-2391
A novel scheme is proposed to achieve self-pumping wavelength conversion for two differential phase-shift keying (DPSK) signals at different wavelengths through four-wave mixing (FWM) effect in a highly nonlinear optical fiber. By changing the phase modulation depths to pi/2 for both of the DPSK signals, the two signals can be multiplexed to generate a differential quadrature phase-shift keying signal. The simulations and experimental results demonstrate the feasibility of phase manipulations for phase-shift keying signals through the FWM process 相似文献