Performance of DRA with different pumping schemes based on coupling equation

After the coupling equations of co-pumping,counter-pumping and bidirectional-pumping distributed Raman amplifiers(DRAs) are theoretically analyzed,the power distributions of these three DRAs are acquired with numerical analysis.The performance factors,such as net gain(NG),amplified spontaneous emissions(ASE) noise,double Rayleigh backscattering(DRB) noise,noise figure(NF) and optical signal noise ratio(OSNR),are discussed in depth.It can be found that the NGs of the three DRAs are almost equal.The counter-pumping scheme will induce higher ASE.And the co-pumping DRA has greater DRB noise,but its NF and OSNR are both better than the others’.Furthermore,the relations between signal power and NG,NF,OSNR are also investigated.It is shown that the NF and OSNR of the co-pumping scheme are superior to those of the other two schemes at small input signal power.The above conclusions can play a very important role in guiding the optimum design of DRA.     

光转换单元中锁相环带宽的优化

考虑光转换单元(OTU)中锁相环带宽同时受外部输入抖动和内部相位噪声抖动的影响,为克服锁相环带宽选择的矛盾性,本文对其带宽进行了优化设计.在同时考虑外部输入抖动和内部相位噪声的情况下,对锁相环带宽算法进行综合分析.通过改进前人的计算和分析方法推导得出OTU中锁相环带宽的优化算法,分析并得到锁相环路的优化带宽,使OTU的...     

EPON中测距技术的研究

以太网无源光网络（EPON）将千兆以太网与无源光纤接入的优势相结合,实现低成本、高速、远距离接入。EPON中光分路器耦合器（Splitter／Couple）与每个光网络单元的距离各不相同,传输延时也不同,来自不同ONU的数据帧可能在OLT处出现碰撞冲突。为实现EPON系统上行TDMA接入,用OPNET创建了一个光网络节...     

EPON中测距技术的研究

以太网无源光网络(EPON)将千兆以太网与无源光纤接入的优势相结合,实现低成本、高速、远距离接入.EPON中光分路器/耦合器(Splitter/Couple)与每个光网络单元的距离各不相同,传输延时也不同,来自不同ONU的数据帧可能在OLT处出现碰撞冲突.为实现EPON系统上行TDMA接入,用OPNET创建了一个光网络...