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101.
The performances of nonlinear WDM systems with different duty cycle are compared by means of numerical simulation.The numerical results show that the optical pulse with duty cycle of 0.5 is superior to the conventional NRZ modulation schene.The conclusion is different from that of some references.The reason is that inter symbol interference is not included in some references.In fact,inter symbol interference plays an important role in monlinear WDM system.Although the larger the duty cycle is,the stronger the effect of the cross-phase modulation and self-phase modulation on nonlinear WDM is however,the larger the duty cycle is ,the stronger the inter symbol interference is. 相似文献
102.
Jong‐Hoi Kim Hyun‐Soo Kim Eun‐Deok Sim Kang‐Ho Kim Oh‐Kee Kwon Kwang‐Ryong Oh 《ETRI Journal》2004,26(4):344-350
We propose a filter‐free wavelength conversion using a Mach‐Zehnder interferometer with monolithically integrated 2×2 multimode interference semiconductor optical amplifiers (MMI‐SOAs). The device has been optimized by considering a non‐homogeneous carrier distribution due to the self‐imaging properties of the MMI‐SOA. Static measurements show an extinction ratio of up to 18 dB and an input signal rejection ratio of up to 20 dB. 相似文献
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本文介绍了大功率IGCT三电平变流器系统的主电路结构及控制系统的设计,实验结果证明该系统结构可靠、运行稳定,将来可以应用到大功率冷轧机传动系统中。 相似文献
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电力电子设备在线故障分析是人们十分关注的课题,科技工作者在这方面常遇到许多困难,复杂性是对研究对象复杂程度的客观度量。本文分析了电路故障的混沌特性,借助这种新的复杂性分析的方法,利用综合性信号监测电路状态,可作为系统可靠性预测的手段。 相似文献
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In this paper, a new algorithm for wavelength assignment has been proposed and its performance is evaluated in terms of blocking probability and fairness. It has been shown that the proposed algorithm offers the least blocking probability. The blocking performance of wavelength division multiplexing (WDM) network has been analyzed for the network having 10 nodes and for varying loads. As the load per link (in Erlangs) increases, the blocking probability increases. The result shows that the performance of first-fit algorithm is better than random algorithm whereas the proposed algorithm offers the least blocking. 相似文献
110.
We present a novel system of a Gaussian soliton generation using a 1.30 μm optical pulse in a nonlinear micro-ring resonator system, which can be used to form the soliton pulse trains within the new wavelength band. By using the suitable parameters, the soliton pulse trains with the center wavelength at 1.30 μm can be generated after the intense Gaussian pulse is input into the nonlinear micro-ring resonator system. The initial pulse bandwidth is enlarged and the signal amplified by the nonlinear Kerr effects type within the ring resonator. The simulation values are used associating with the practical device parameters, whereas the obtained results have shown that the wavelength enhancement of the center wavelength can be achieved. Furthermore, the maximum soliton output power of 12 W is obtained, which is available to perform the long-distance communication link. The common problem of soliton dispersion is minimized by the zero dispersion condition in this case. The major advantage of the proposed system is that the dense wavelength division of the center wavelength with the spectral width of 7.0 pm (10−15 m) and the free spectrum range of 400 pm can be generated and achieved. This is available for the used/installed wavelength enhancement, which can provide more available channel capacity in the existed public optical network. 相似文献