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光纤喇曼放大技术及其应用 总被引:2,自引:0,他引:2
概述了光纤喇曼放大器的发展情况、分布式喇曼放大器的原理和特性 ,重点阐述了掺铒光纤放大器与喇曼放大技术的组合应用 ;最后指出 ,这两种技术的组合应用能明显提高长距离光纤通信系统性能 ,使掺铒光纤放大器具有更广阔的应用前景。 相似文献
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首先介绍了波分复用系统中混合光放大采用的喇曼放大技术的原理及系统设计要素,然后介绍了喇曼光纤放大器的应用及对传输系统的改善。 相似文献
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随着10Gb/s DWDM长距离传输系统的大量应用和40Gb/s技术的日趋成熟,喇曼光纤放大器的重要性日渐显露,并逐步进入商用。光器件制造商竞相研制出了性能优良的喇曼光纤放大器,主要是希望利用喇曼光纤放大器特有的分布式放大,可降低非线性影响、噪声特性好等特点,进一步推动高速,大容量,长距离光纤传输系统的发展。 相似文献
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对由普通单模光纤 (SMF) ,色散补偿光纤 (DCF)作为喇曼增益介质的两种结构的混合链路光纤喇曼放大器进行了实验研究 ,并对实验情况下的实际传输系统中的混合喇曼放大链路进行了理论数值模拟 ,比较和分析了两种链路结构的增益和噪声特性 相似文献
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光纤喇曼放大器的发展与应用 总被引:1,自引:0,他引:1
首先介绍了光纤喇曼放大器的发展情况和原理结构,与掺铒光纤放大器相比,指出光纤喇曼放大器的优点,然后在三种不同环境下,对混合FRA/EDFA放大与EDFA单独放大这前后两种放大技术的QoS性能进行了比较,最后介绍了FRA在SDH、CATV、WDM和企业存储网络中的应用. 相似文献
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摘要喇曼光纤放大器具有低噪声、宽带宽等新一代光放大器的重要特点。介绍喇曼放大系统软件的数学模型、器件模块设计和运行流程,喇曼增益仿真结果与实验数据均方误差小于10%,可以很好地应用于喇曼光纤放大器的设计。 相似文献
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Aiming at the different requirements of energy transmission and information transmission in simultaneous wireless information and power transfer (SWIPT),an opportunistic transmission scheme was proposed for enhancing physical layer security.Firstly,a SWIPT network with multi-cells was considered where multi-users,multi-eavesdroppers and the users were assumed to adopt time-switching based receivers and employ non-linear conversion model to harvest energy.The transmitter could dynamically switch between information transmission and power transfer according to the channel state,breaking the traditional fixed slot allocation scheme of energy transmission and information transmission.On this basis,the performances of energy transmission and information transmission were analyzed comprehensively,including the stability and efficiency of energy transmission,and the reliability and security of information transmission in the scenario of independent eavesdropping and joint eavesdropping.Next,a switching threshold optimization model was given to maximize its secrecy throughput under the constraint of the energy transmission,the reliability and secrecy performance requirements of information transmission.Finally,simulation results verify the validity of the proposed scheme. 相似文献
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In order to solve the problem that many existing resource-transmission-based methods ignore the important influence of the matching degree of two endpoints on resource transmission,a link prediction method was proposed based on matching degree of resource transmission for complex networks.Firstly,by analyzing the two endpoints on the resource transmission path in detail,the method of quantifying the matching degree between two nodes was proposed.Then,in order to describe the influence of matching degree on resource transmission process between nodes,the matching degree of resource transmission was defined.Finally,based on the matching degree of resource transmission,a resource transmission matching index was proposed considering the resource amount of bidirectional transmission between nodes.The experimental results of nine datasets show that compared with other similarity indices,the proposed index can achieve higher prediction accuracy under the AUC and Precision metrics. 相似文献
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为了提高输电线路缺陷诊断正确率,有效降低各种复杂背景纹理及光线对识别输电线路结构的影响,从Gestalt感知理论着手,研究一种多感知识别输电线路结构的方法。在图像识别的底层,提取不同方向、不同宽度的线段,研究了一种融合计算Gestalt定律的近似性、连续性、共线性的多级搜索算法,获得显著的、完整的输电线路人造对象轮廓;在图像识别的中层,研究一种基于分块与合并的计算方法能视觉感知近平行线、近对称交叉的结构,设计了一个三级分类器感知聚类平行线组;在图像识别的高层,研究输电线路的知识模型,建立识别输电线路组成结构的约束机制,进而从语义上唯一地识别输电线路的结构。通过无人机巡检采集的输电线路图像,验证这种方法能有效识别输电线路组成的杆塔、导线、地线及绝缘子所在区域。 相似文献
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In order to solve the problem of the high requirements of data transmission rate and sensitivity to transmission delay in virtual reality (VR) based on cloud services,a Cloud VR system with MEC (mobile edge computing) was proposed,mainly including viewpoint-based VR processing and HDA (hybrid digital-analog) transmission optimization.Firstly,a dynamic streaming method based on user viewpoint and pyramid projection was used to implement a complete edge cloud VR system.Then,HDA transmission was introduced to optimize the transmission,and a heuristic algorithm for resource allocation was given.Finally,the base station protocol stack was transformed,and the MEC was integrated into the LTE (long term evolution) system to implement a complete mobile edge cloud VR system.Experimental results demonstrate that the proposed scheme has good robustness and efficient transmission by comparing with the existing schemes. 相似文献
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为了解决无线链路易出错从而降低传输效率以及由于重传导致数据流间传输不公平,基于网络编码的思想,在无线单跳传输结构下,提出了基于编码组的传输模型,并根据中心站点的传输数据不同,分为内部数据传输模型和外部数据传输模型.基于上述传输模型,提出了一种基于编码组的数据传输框架.最后通过仿真实验,分析了ARQ单播策略、FEC单播策略和编码组传输框架的传输延迟,同时还对它们的传输吞吐量进行分析比较,并且在节点突发出错情景下分析ARQ单播策略、FEC单播策略和基于重传的编码组传输框架的吞叶量变化.实验表明:FTCG能够提高传输效率,并且在节点突发出错情景下能有效解决由于节点突发出错而造成的系统吞吐量急剧下降问题,保证了数据传输的公平性. 相似文献
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The mismatch of transmission ability causes the discontinuous transmission of video services in fiber-wireless access network,aimed at this problem,an QoE-aware video distribution mechanism was proposed.According to the structural characteristics of fiber-wireless access network,link state information and scalable video coding structure was considered,a QoE evaluation mode was established,and the particle swarm optimization algorithm was used to select optimal video transmission rate.Then the node transmission capacity and the node matching degree was analyzed,transmission path for the services was selected,so as to ensure the reliable transmission of services.The results show that the proposed mechanism can effectively improve the utilization rate of network resources and reduce network congestion while improving the quality of the user experience. 相似文献
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为了保证紫外临边探测光谱仪圆满完成工程任务,实现对地球临边光谱的观测研究,设计并实现了通讯与数传系统。首先,介绍了通讯与数传系统的构成及工作原理;其次,对通讯功能进行详细设计,提出一种基于通讯超时和数据错误的故障诊断与处理方法;然后,对数传功能进行详细设计,提出一种基于8b/10b的数据传输方法;最后,对紫外临边探测光谱仪在轨飞行的实验结果进行分析。实验结果表明:通讯与数传系统实现了高可靠的指令通讯及科学数据传输;环形成像仪的数传频率为80MHz,前向光谱仪的数传频率为40MHz,性能测试结果满足技术指标要求;RS-422串行通讯过程中,字节间延时误差不大于2ms,接收消息与反馈消息的延时误差不大于5 ms,有效提高了系统通讯的连续性、及时性和可靠性。 相似文献